the 9500pro is much faster than the Ti4200
the 8x agp of the Ti4200 gives no performance increase over the 4x version. check out the articles under the graphics card section at THG. the results show this clearly
the reason I say the 9500pro is better is because its a generation newer than the TI4200, and has roughly 2x the performance for DX8 effects. Im NOT saying 2x the performance in general, but the geometry and effects engine of the 9500pro has roughly twice the output.
this translates into higher framerates in future games (not many games nowadays take advantage of the 9500pro, thats why people are comparing it to the TI4200, which will be noticeably slower in games 6 months from now) and less upgrading