A quick word on Odyssea (oddy-sea?

) - you don't want their 175W setup. Essentially, they're using a 150W Double ended bulb and overdriving it using a single-ended ballast to 175W.
Doing this will alter the color characteristics, as well as siginificantly lower the bulb life.
Also - the bulbs that come with them are pretty bad. The "20,000K MH bulb" isn't 20,000K and the actinics are DEFINITELY not actinic. Replace the bulbs ASAP.
That said, I have their 150W unit (with the proper ballast) and really like it.
I haven't seen a lot of their older fixtures, but am of the opinion that their quality has improved dramatically over the past year.
I would have absolutely no problem using one of their PC fixtures and would use MH with no problems as long as the bulbs were replaced.
But then again, I'd replace the bulbs on the PC as well.
As far as their T5's go, I wouldn't touch them. Their reflectors are crap, and the ballasts are terrible.