I have one of the MA planes and have used the GP powered one a little bit. I waasn't happy with either one. I had one from many years ago that used to work fantastic but I had ran out of blades and couldn't find them anymore. That's why I was trying the others. Anyway I just found a supplier for my old one. It's called a David Combi-plane and it's really inexpensive, relatively speaking. I just got a couple packs of new blades in the mail today from,,,,

http://www.freeflightsupplies.co.uk/

It's out of the UK but they have lots of little tools and other items that may come in handy for some.
I placed my order last saturday, paid via paypal and I got them today. I'm very happy with my fresh blades!
later,,,basmntdweller