You should purchase 3 pros for your 30 gallon aquarium. I had 9 over my 90 gallon and that worked out well. If I were you, I would purchase 1 x Blue/magenta, 1 x blue, and 1 x blue/white. That was a very nice color combination for my tank. The 2.0 pros are nice lights, I do not think you would no be wasting your money, nor do I think you could buy a better light for the money unless you do a diy Cree LED kit.
If I were you I would only purchase one 60 watt transformer, a 3 way splitter, and a dimmer to control all three lights at the same time. That color combination is nice and I don't think you would need to control each light individual unless you wanted to to change the spectrum, but that makes it a lot more expensive. You can also email Ecoxotic and ask them what they would recommend for your tank.