I have a Boomerang, and off the top of my head I can't think of anything I don't like about it. Maybe it's size, but that's only for transport, if I didn't have a trailer I would get tired off breaking it down to fit in the pickup or car or whatever, I think it would probabally fit in a pickup with an 8' bed however. I don't know what the larger facet would sell for, but the boomerang will most likely be the most expensive to get in the air, and from the amount of time people are reporting it takes to build the AV8R or a Facet it probabally will take a bit longer to build. It is not hard to build, but there is just alot of it to build . It would take about any turbine you would want to put on it, I believe Alan said he even flew his with a Wren 54, I am at 5000' and don't believe I would want to power it with anything less than a 17-20 lb class turbine, mine is powered by a P-120 and hopefully soon a P-160, the 120 works great but I would like a bit more vertical, mine is around 30lbs wet. As for flying the boomerang, its a piece of cake, I fly it off of 400' easily and it will do anything I am capable of making it do . It will fly amazing slow and also has a fair bit of speed, but by no means is it fast maybe 120 or so tops, maybe not even that when I first installed the P-120 I set the limiter for 120 and according to the gsu I never got close.
I can easily say the Boomerang is one of the best flying planes I've ever owned, I don't think you can go wrong with any of the three though, if you decide on the boomer and have any further questions just ask.

Regards Jack