BCV, BWV, and VWL (Boulder Ridge): studio room sizes are very close to each other, just under 360 sq ft. The room has a queen and a double-sized, pull-out couch, single bathroom with combined tub and shower, and the murphy bed which pulls out of a large cabinet, above which is the TV; for all three that murphy bed was something added not too long ago. Points required are very close to the same at each resort, except that BWV has "standard view" at a significantly lower cost. Those are limited in number and considered the best DVC bargain at WDW -- you get a near park resort and can walk to two parks at a cost that compares to OKW. -- but they are often hard to get unless you book right at 8 a.m. eastern at 11 months out. BWV also has boardwalk view as a booking category and those rooms have fantastic views but can also be difficult to get unless booking with the 11 month window.
Poly and VGF: Poly has the largest studios at 465 sq ft and VGF comes in at about 374 but much of the Poly space is devoted to the bathroom areas, with the result that its sleeping room is comparable in size to VGF. Both have a queen bed and a queen-size pull-out couch, and the murphy bed; both have split-room bathrooms, with a combined tub and shower and a separate shower. Both have a room point cost significantly above BCV, BWV and VWL. Poly is the only DVC resort where you can get connecting studios (every Poly studio except two connects to another studio). Currently connecting studios at Poly are not guaranteed but probability of getting them is very high. To get a studio at VGF often requires use of the 11 month booking window and there are times when you need to book at exactly 8 a.m. at 11 months out to get one.
Note when you mention WL, I am assuming you meant what was formerly VWL, which is now Boulder Ridge. If instead you were referring to the new Copper Creek Villa rooms in what was a portion of Wilderness Lodge hotel, then those rooms do not have the murphy bed and allow 4, most are only 338 sq ft but there are a small number of "alternative" studios that are actually around 400 sq ft. Also, the bathrooms for the studios can have either a tub and shower or just a shower (that is a guaranteed booking category)
