Look over in the battery forum at rcgroups. There is a decent size thread on this charger. I've had mine for a couple months. Various thoughts:
1. Build quality is decent. The first unit I bought has worked well although one of the fans is making noise. Like the bearing is going out. The second unit I bought literally had the LCD hanging out of the case. Looked like it was packaged that way. I got a refund from the seller.
2. The charger is made by the same OEM company that makes the Hyperions (SJ Propo).
3. There has been some debate whether the charger will actually output 300 watts per side at the same time or not. From what I have seen nobody has proven it doesn't but nobody has tested it with a 24v power supply.
4. Unless the seller is going to offer you a warranty I would say warranty is non-existent.
The Hyperion SuperDuo is scheduled to come out sometimes in May for a rumored price of $280. With shipping the MegaPower charger is usually over $200 which makes it a questionable buy when compared with the Hyperion which would have a warranty. Of course the Hyperion thread over at rcgroups has people reporting hardware problems with the Hyperion chargers. Also, from what I read any warranty work on Hyperion units has to go through the point of purchase. Not ideal in my opinion.