I would agree with the others you were talking to: The C40 is a bit outdated, is only PWM operated, and even the ratings are a bit confusing (C40 = 40 amps solar, but only 32 amps wind diversion, shucks).
But the MPPT Tristar and Outback definitely cost more. Decide now: either you are committed to expanding your system in the future, or this is just for fun and tinkering and you don't need the max of the maximum to be satisfied. Depends on what you want out of the system.
For my example, I have a Tristar TS-60 for wind, a C40 for solar, just the PWM models. My batteries are for backup, not really for daily power, so they're always at float, and the solar I have is enough to maintain float charge sun or cloud. Getting a MPPT controller wouldn't do any good for me. If I changed the purpose of my system, then these needs would change too.