I just bought this system. I know a lot of people don't like digi's right now, but I do. I like that the ballast is only warm and it is fully dimmable, so I can turn it down when I need to. It was super affordable and the people at Flora are easy/good to work with.
http://florahydroponics.com/product.aspx?id=3021
I did have an off-brand from Amazon, and went through 2 of them in one month. The ballast kept frying itself. I literally had to use potholders to move it, I gotta tell ya scared the shit out of me, I was like, I'm gonnna come home one day and my house won't be there lol. This ballast has a 3 year warranty and Flora stands by their stuff, so for 135.00 for 400w, I think it is pretty affordable. I bought the 600w system for 175.00. The digital ballast runs BOTH HPS and MH, so it is a good deal, but be sure you buy a bulb that is set up for a digital ballast cuz they run at a bit higher frequency than the mags. I have used cool tubes and such in the past but never had good luck keeping them cool even with expensive fans, I like an open system much better, the heat disperses more evenly.
I agree with you on the t5's also... Lemme tell ya that's the only thing i use to maintain moms and veg., I won't ever give up my t5's, for back up etc., I have 2 4 tube systems.