I Haven't tried this way so don't take what i say to heart...
Cons:
-Wheel would have to be huge, unless you grow small plants, Depending on the strain you grow...
-possible lighting problems since its a wheel, if u put light in middle it wouldnt be as direct...
-Once plants get big enough they might get too crowded and not get enough light
-depending on soil medium you use roots might dry out on the cycle if its too slow
-Some look pretty Pricey
Pros:
-Can be used in small space
-Looks pretty self sufficient
-if you wanted to you could mod it and add misters on a timer
-Looks cool
-Some of the ones i looked at are pretty damn nice and are all inclusive
If you ask my opinion right now im 50/50, it looks pretty plausible with a few possible flaws, but if you want it, Try It! and tell us how it goes
Here is a pretty good setup>>(expensive though)>>
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=200363180166&rvr_id=&crlp=1_263602_263622&UA=WVS?&GUID=181201601250a0e203211c91ff206a4f&itemid=200363180166&ff4=263602_263622
But like i said before, i havent tried this or seen this, i just looked at the pics, specs, and what it includes and guessed, so dont let my opinion persuade you too much...
Good Luck!