Those doors are different! Does the rustic look go with the current feel of the house? It's easier (probably) to install new doors which would then have to be painted or stained. But you won't find anything of that quality (as far as I can tell from here of course) in a mid range door. But you have to like them, and they are definitely a strong design feature so if you don't like them, they'll probably bug you. They do look like redwood and they look like they wouldn't sand well. Can you test a closet door inside? If you COULD sand and finish them, they could be stunning. I don't think they'll be any lighter though--that's probably their natural color.

Basically, MDF is less prone to movement(expansion/contraction) due to seasonal temperature changes than solid wood. The construction of a raised panel door necessitated the panel be installed without glue/fasteners to allow for that seasonal movement. An example of allowing =for that movement in a dining room table is when the builder makes slots for the fasteners between the top and base instead of locking the top to the base with screws/glue. However, most MDF will retain moisture when in a wet condition----standing water is a flooded basement---for instance. There is a possibility, IMHO, that dripping water off the counter could land on the panels and seep into the groove made for the raised panel. Enough of that and the MDF would swell, causing the rail to crack. The type of wood used also has a bearing----oak is less absorbent, but looks terrible(IMHO) painted without filling the grain. Maple is good, poplar absorbs moisture more easily. It boils down to the climate and uses in your kitchen to determine the construction materials---as well as your wishes. Sounds to me like you'd rather have the wood---and real wood raised panels for the same price as MDF panels is a good deal----or the MDF panels are way overpriced.

You said you ordered the Doors wood with MDF panel - that will not eliminate the paint fissures from expansion and contraction - the wood parts will still move. The mdf panel helps because it is not moving but it is not the cure all. I have a company who does doors made of all MDF but put together like a regular door is and while the paint lines are minimal they are not marketing the product as not ever getting those lines. It will still be possible but much less. As far as chipping goes, I think that will happen no matter what the door is made of. Have a conversation with your KD and see what the real deal is and go from there....Maybe they will let you use one of the doors as a test... bang it around, bump it with pots, soak it with water, spill stuff on it and see what you think ( but you should try that with wood too....) Good luck!

MDF is usually medium to light brown in color and has no grain nor does it have any definition. Pressed board and chip board(both being a different color and both having easily seen particles because the materials are made by treating particles/wood chips with adhesive and curing under pressure and heat) are not MDF and should not be confused as such. I have seen OSB referred to as MDF, which it is not. The major problem with MDF is the holding power of screws is much diminished because of the nature of the material. That is why, at least on entry doors, a MDF core door has a wood insert at least on each side. The door I used has an insert a full 2&1/2" thick on each side. The door is 34" by 80" and probably weighs in excess of 80 pounds. I used 2&1/2" screws on the hinge side for the door and 3" screws on the frame side(which went into the studs as well). MDF may be harder, but the edges chip more easily than wood when impacted. There are also LDF(low density fiberboard) and HDF(high density fiberboard) products. HDF is also called hardboard and is usually made in thinner sheets of 1/8" or 1/4" thicknesses. The darker brown boards with holes(often called pegboard) use for hanging things on is HDF. HDF is also used in cabinets, RV's, and even aircraft, among many other uses. LDF is usually referred to as chipboard or particleboard.There are also medium and high density variations of particle board. OSB is not included in this designation as the pieces are larger and oriented by design to provide more strength.