Why even bother to buy a geforce4 Ti4200? It is NOT going to be any better than RADEON 8500 retail. Think about this, everyone knows that RADEON 8500 and geforce3 Ti500 are in the same range on 3DMark2001 score, and a geforce4 Ti4600 is about 2000 points higher than them. A geforce4 Ti4400 is only within 1000 points range higher than RADEON 8500 and geforce3 Ti500. Then it's easy to imagine What a geforce4 Ti4200 is going to be?? It's probably just about the geforce3 Ti500's performance or just a little higher. I can say the difference between Ti4200 and Ti500 is going to be just like geforce3 Ti200 and GeForce2 Ultra.
Don't say you can overclock Ti4200, because RADEON 8500 is also good for overclocking.
UNLESS Ti4200 is going to be about the same price as RADEON 8500, other wise there is NO reason to spend the extra money on something is about the same performance.
If you really only care about the performance, go for Ti4600. It does make a difference which you can notice compare to the RADEON 8500.
If you cannot afford it, just go for RADEON 8500.
And for most of you, don't cry when you cannot afford a top line nVidia cards anymore by the time the ATI is defeated.(once nVidia beats its last enemy, you can imagine the price of its products). So don't buy "name".
So final answer-------------Ti4600 OR RADEON 8500!!(don't even bother to think about Ti4200 and Ti4400, they both are NOT much better than RADEON 8500.)