KraftMaid are side mounted..

I think that going to Lowe's to see how Kraftmaid are made won't hurt anyone. You may even be able to tell by going to Kraftmaid's website and looking at some pictures. Personally, I don't think side mounted rails are a big deal. I never actually thought about it, though. But just because Kraftmaid does something in a certain way doesn't mean it's the only good way to do something.

My custom drawers have the side mounts too. They're no better or worse, it's just what the guy uses. Go look at some (maybe even what you have now?) and see if it bothers you.

Undermount is considered much more upscale in appearance by most cabinet makers in the industry. I would say he has not been able to state his case very well if you can not re explain it. Side mounted full extension soft close rails are available. I would guess the reason he wants it a certain way makes it easier for him to install them based on the shop he uses.

Kraftmaid are side mounted if you do a standard drawer. The side mounted are not rated to carry as much weight and do not allow the drawer to fully extend so all of the drawerbox is visible to the eye when you open it. Side mounted ball bearing slides will allow this with softclose if you use the right one.

The ball bearing full extension without soft close I would bet is most used in the country for auto mechanics tool boxes.

Statgeek, we must have the same cabinetmaker! Mine was ademant about side mounts & it didn't make any difference to me - it's not like I leave the drawers open to display the sides. I've worked with this man for 20 years & absolutely no one has a higher work standard so I went with his choice as this is definitely his area of expertise; no soft close because I think it's gimmicky. No regrets after 8 years!

Davidinorlando, My side mounts are full extention & the back of the box extends past the face frame. I believe they're rated for either 50# or 100# (I forget which) & I'm sure I could have gotten higher rated ones if I had drawers that needed to be extra heavy. Although they are quite functional, they do not resemble a mechanics tool box nor are they in the country.

I must agree with Antiquesilver--Davinorlando is very much incorrect about the functionality of side mounts.

(And if one ever saw photos of Antiquesilver's kitchen, one would also say he's incorrect about them being low-end.)

see the difference between

Blum Tandem
Blum Tandembox

One is under the drawer.
One is on the side of the drawer.

They both are very good value. It IS possible to have expensive high quality slides under the drawer, invisible (not showing) when you open the drawer.

Hth

I feel we have more drawer space with our under mount glides. We had side mount in our previous cabinets and the new drawers (under mount) net us more usable space. Arguably, it's not much, but we have a small kitchen and every inch helps.

I was refering to side mounted rails that are used by Kraftmaid which are side mounted expoxy coated rails with plastic wheels that slide down the tracks which are 3/4 extension. I am not that stupid to presume to know what the side mounted rails are like that are in your supposed custom kitchen. This thread is a good example of the blind leading the blind on here more often then not.

For the info of anyone who wants to learn something and not continue to spread miss information soft close has an engineering purpose. The cabinet companies do not put them on cabinets to make you think they look cool. When you build a cabinet drawer to be rated for 100 lbs or more in weight the cabinet maker adds soft close mechanism so it is not possible to slam the drawer shut and crack the face frame of the cabinet.

A side mounted full extension slide in an of itself is not superior an undermount full extension glide. I have several cabinet companies I sell that use them. They are not easy to slam shut they way they are made. They also have rubber bumper at the end of the track in the back of the cabinet which holds the drawer shut when you close it.

Every cabinet I sell with side mounted full extension glides are the same as those on Husky, Kobalt, and craftsman mechanics tool boxes I keep my tools in.

If you made cabinets that you are going to provide a warranty for, and you make the drawers to be rated for 100 plus pounds, would you want to warranty the cabinet frame would not fall apart in a home with domestic violence? The drawers would be slaming shut everytime someone is mad at another person and lets out their frustration on the drawers and doors. Their is a reason people make things the way they do. Just as I stated in the first post their is a reason the guy wants to use the side mounted that the person with the original post did not understand to restate.

To the OP: Soft close comes on undermount too. One response you received was: "Undermount is considered much more upscale in appearance ...." to which I agree.

Quoting OP: "We are working with a custom cabinet maker who insists on side mounted drawer rails. .... But what do you think?"

I'll have to agree with the person who wrote that your guy must have some personal reason why he doesn't want to start buying and learning how to install undermount glides. Notice that he wasn't able to give you any reason worth its salt. Not only could you not reiterate it (probably because it was confusing) but nobody has offered any reason why sidemount need squarer boxes or are somehow truly better.

"I'm told his prices are remarkable ..."
Compare
$30
550mm length Tandembox C high, steel back plate, chipboard floor
http://www.ikea.com/us/en/catalog/products/90109977
You put the drawer front you want on it; any height.

Softclose dampers (Blumotion) bought separately.
http://www.ikea.com/us/en/catalog/products/60108677

If the drawer is to fit inside a larger one, here is the internal drawer front. http://www.ikea.com/us/en/catalog/products/20132387

I would recommend the Undermount Softclose Drawer Glides. Don't accept anything but "Blum". there are many other generic tracks on the market but all fail in comparison.

These are the only tracks I would use in my kitchen. The other tracks are outdated.

Thanks everyone for all the responses. The cabinet maker's inflexibility was almost a deal breaker but then my husband and I decided that he was working with us on other aspects of the cabinets and we would let this go. Metal side rails are definitely not our preference. We investigated 3 other cabinet makers, two which handed us a disclaimer about wood variation which made me nervous. The 3rd's quote was more than we felt we could afford. We want natural cherry doors and this cabinet maker is going to work with the wood to minimize the amount of sapwood showing on the door face--so no disclaimer, just better attention to that detail. In light of that consideration and other custom features, we're going to live with the side rails.