I was trying to avoid having to buy a sub(s) by getting the 310s.... I have a super ultrawide 49" wide monitor on my desk, which makes speaker placement a bit tricky.
Even if you had 310's, I think a 150 + 750 will give you an objectively better sound than the 310's with no sub. 310 + sub would likely beat out the 150's + sub (as they should)