Being that this is a TDM plug-in, the TC Electronic Megaverb doesn't run on your computer and will only run off of your HD systems processing power. For this reason, I can't say that I had any problems at all running the plug-in in the Pro Tools HD system that I used it in. I always run reverbs and delays on auxiliary channels anyway to limit the amount of processing power being used, regardless of if I'm using it in HD or LE. I'd suggest doing this, but if you have this TDM version of Megaverb, you're probably going to be fine either way.
There are certainly a high number of reverb plug-ins to choose from out there, and while the TC Electronic Megaverb TDM/HD plug-in isn't my favorite, it is definitely still worthy of a look. It has a very clean sound quality that can be manipulated in all sorts of different ways. I do however think that the plug-in is a little bit overpriced, as there are some plug-ins out there for the same price and cheaper that I like using better. If you are a home or professional studio owner looking for a reverb plug-in, I'd definitely suggest trying out as many different ones as possible, including TC Electronic's Megaverb.