Oh boy! That's a tough one because I have the 24-70 and the 50 1.4 and 85 1.8 and I just got the 70-200. I started with the 85 and added the 50 a few months later. Both are amazingly sharp and so easy to use indoors. But the 24-70 is my most used lens. I keep it on my 20D and 2.8 is not bad. If you don't like changing lenses often and you want one of the best zooms out there, opt for the the 24-70. If you don't mind changing lenses a lot and using foot zoom, as Pekka calls it, then the primes are, IMO, a better choice. Sometimes I wish I could have 3 camera bodies all the time because I don't like to take time to change lenses at events, but I'm limited by what I can take into a concert, for instance. So the zooms are my better choice.