I use the 27.20's they work with the refreshrate fix ,and work with GF4 ,the 27.50/41/ect......... Dont work with the refresh rate fix ,from my experience.
WWW.3dchipset.com has the 27.20's ........ my 4400 is a 4600 now ,going for more soon.
There is a BUG with the gf4 ,currently ,2 I know...