Just realized I answered this purely from a 2-channel audio perspective since we're not in the home theater forum area. Considering this looks like it'll also be used for home theater I think the idea of mating 60s with a sub makes a lot of sense (you'll need a sub for HT anyway, regardless of which model you choose). You could get the 60s (or maybe even the 40s or 20s) and something like a Hsu STF2 subwoofer and potentially be much better off overall. You'll have deeper and even more impactful bass for movies and probably a better and more full-range bottom-end foundation for music as well. Plus you get the flexibility to place the sub where bass can be optimized for your room -- something you can't do with tower speakers alone.
I'd let your budget determine which version to purchase. Yes the v4s probably offer some improvements, but I highly doubt you'd be unhappy with v3 or even v2, and if it allows for less financial stress or even a better subwoofer you might be better off. I'm thinking for the same money as the 100s you could do the 40s with something like an SVS sub or 2 Hsu subs (if room allows) and have some pretty serious full-range performance for both music and movies. The possibilities are endless, and maddening.
Best of luck.