Lacking the extra math of the register combiners, the specular highlights don't look as good as on a GeForce. Most of these except the V5 probably won't have enough fill-rate to be very enjoyable. The game will probably run, but it won't be anything like we intend it to be viewed. Almost certainly not enough fill rate. Maximize the resulting values for an amount of effort you are willing to expend.
Computer games do have some notable aspects of their own, though.
Riding the wave of Moore's Law causes timeliness to take on a couple new facets. Every once in a while, new things become possible or pragmatic for the first time, and you have an opportunity to do something that hasn't been seen before, which may be more important than lots of other factors combined. It also cuts the other way, where something that would have been a great return on the work involved becomes useless or even a liability when you miss your time window. Several software rendering engines fell into that category.