theplayer... it is confusing. Here is what I have learned: The old style looking RCS with the slotted vents on the front were configured with the simmer, 2x15k and an 18k burner. The new style RCS without the slotted vents in the front (like I bought) have a simmer and 3x15k burners as a way to cut costs. When we were in the process of purchasing this new style RCS the on-site BlueStar rep was hawking the new style range as having the simmer, 2x15k and an 18k burner... the rep was apparently not educated on the new style burner layout and telling us the burner layout was the same and did not change from the old style RCS. Since the 18k burner was the selling point for us to buy this new style range, along with the new look, we held the appliance store to the rep's word. In short, the new style RCS does not come with an 18k burner unless it is ordered as an upgrade.

Call them. I had calls returned promptly on a couple of occasions when I was shopping this winter, and then buying early in the spring. Others on the appliance forum have also posted good feedback by phone from BlueStar, from Mandy among others. There are threads on the appliance forum that discuss some of the differences between the RNB and the RCS, as well as departures from the norm with the Costco (and other special run models) of RCS. The ranges are similar in many respects, and there are threads about "hot-rod" modifications to boost the output of the RCS burners as well (search for these and mojavean). Off the top of my head, I don't recall whether the Costco RCS has a convection oven, but you likely know already. The newer RNB ranges have the high output burners and better insulated oven doors. They also offer a choice of color. With an RNB order, you also have quite a few options when it comes to specifying the details -- for instance, on our 36" RNB, I had them move the left-hand supernova burner from the front to the rear, bringing the simmer burner to the front of the range -- works well for me and the upcharge for the custom arrangement was very small. OTOH, the RCS offers a very attractive option -- an open-burner range that shares many attributes of the RNB at a very big discount.

Big box and discount stores often have a different number. Sometimes there are slight differences in the model, others it's just an identifier that you got it at Costco. Maybe do a shout out to Trevor or Jakvis who might know how to unpack the model numbers? From looking at the listings I've been able to figure out that the "30" is for a nominally thirty inch wide range. The 4B seems to be for four burner. (The 36" one is 6B.) I think the V2 is for the height of the back--vertical level two. (edit: Correction from John_Williams50--V2 is for Version 2) "SS" on other appliances is often "stainless steel", but I don't know if that's so for BS. If so, "C" near the end would be for "color".

We've had our 30" BS RNB for eight or nine years now. I have used the oven extensively and find that it is very reliable. It does exactly what it's supposed to do; nothing more and nothing less. I like working with it, other than the fact that it takes really long to pre-heat. The fact that it is so predictable makes it a joy to bake with. I usually store my large Fibrament baking stone in the oven and don't take it out when I use the oven. I don't think it makes a huge difference for everyday use, but it might contribute a little to my overall very positive impression of the oven. In general though, most ovens benefit from a) more thermal mass, and b) dispersal of thermal energy. So, I almost always keep either a baking stone or at least a cookie sheet on the bottom shelf of any of the ovens that I have ever owned. Having said that, we now have a Miele combination steam oven and a Miele SpeedOven in addition to the RNB. I find the SpeedOven isn't much of an alternative. I am happy that I bought it as an extra oven that happens to use the same space as the microwave; but I am not sure the cost is quite justified by the benefits. So, don't buy, if money is tight. On the other hand, the CSO is a huge improvement over anything I have owned before. It preheats much faster than the RNB and the fine-grained moisture control is awesome. The smaller cavity size is rarely an issue. I now use the CSO for everything. The only downside is the rather anemic broiler element. These days, the RNB only gets used if I need a good broiler. None of my other appliances even come close.