Well $110-120 for 4200-64MB, $130-150 for a 4200-128MB, 4400s (including MSI) are now quite easily found under $200 while the 4600 cards come in at $225-235. That's far more realistic, where do you shop! In fact the 4200-64MB can be had for as little as $100, see
HERE
I agree that it's not worth buying a 64MB card, but the 4200-64MB do use 3.6ns which gets from the default of 250/500 (core/RAM) to about 300/600. The 4200-128MB hardly use slow RAM, 4.0ns is standard and gets from 250/444 (which is only 2-3% slower than 4200-64MB @ 250/500) to 300/550 which is beyond 4400 perf, that's not slow at all. Finaly there is the enhanced 4200 -128MB cards using the longer 4400/4600 design and BGA RAM, although they use higher standard clocks and o/c to 4600 levels and beyond they do come in at 4400 pricing.