Okay...VHO or Power Compact

[BCOrchidGuy]

I don't buy any tubes or bulbs from the LFSs you can get most everything from either home depot or brite lite and save a ton of $$.
I also grow Orchids, I know you would never know it from my nic (sarcasm), but with them I can see a huge difference when I change over to a new bulb, especially when I change a 5500k bulb (MH) at 6 months of bulb life. I have half of my plants in spike 3 to 4 weeks after changing out the bulb. The bad thing about intensity is that it drops so slowly that it is hard to notice with your eyes, unless you are using a light meter on a regular basis I assume that you would never notice the change in intensity. Even the manufacturers tell you that the bulbs loose 10% + after burn in, that is why they give you an initial and a mean output.
Perhaps the electronic ballasts do make a big difference, I can't comment on that, I would like to get a quantum light meter though and track the changes in tubes and bulbs over a period of a year to a year and a half I think it would be interesting.