I have to agree with everyone when it comes to the Federal RS-R, When it comes to dry grip for money, there is nothing better. Dereck and Fifth Gear use the RS-R on the track aswell.
I've used a bunch of tyres on and off the track (and skidpan), and I don't use anything but Bridgestones and Federals anymore, and if it wasn't for the fact federals don't make a 225/50 r16 I would use them all the time.
Anyway these are honest opinions of the tyres I've used
Federal
-595RS-R Excellent Dry grip, good K's for a sticky tyre, and predictable in the wet (and dry) and NOTHING better for price, great for track use
They make every tyre size EXCEPT FOR 225/50 R16 (17's are coming, dont worry)
-595SS Good Bargain street tyre, Last really well and quiet
Bridgestone
-RE001 Best cold start STREET tyre I have used, Not as grippy as the RS's in the Dry but V.good in the wet. K's no better than RS's when driven hard, but handle abuse well, fairly expensive
-RE050 Almost as grippy as RE001's in the dry, better in the wet and Super expensive and don't handle abuse well
Recommend Track use
-RE55 SUPERSOFT Most grip I have ever have wet or dry, little slippery for first KM, Don't last more than 1000kms, really expensive
-RE55 Hard Will never get to temp on the street and never get to grip, great track tyre
Goodyear
-Eagle F1 Assymetric, average dry grip, squealy, superb in the wet
Khumo
-KU31 Cheapest tyre i would almost recommend, don't last long at all, Federal SS's do everything better.
Dunlop
-Imported Z-01, Crap, anything that has been used and then stored or improperly stored, seems to be crap
Depends on what your after really