Well kh6oo--you asked!

Try to take it all with a grain of salt. Lots of different users + lots of different circumstances + lots of different performance requirements = lot of different opinions.

I have to add my support for the Magnums. In my experience, they're a great value for the money. Mine have all been easy to tune and run like champs on 15% Wildcat or 15% Omega fuel. Good performers and easy to maintain.

If it were me, I'd see how much weight it takes in nose to balance the plane. I'd then purchase either the Magnum XL-52RFS or XL-70RFS depending on which one is closer to the weight needed. I'd hate to install a Magnum .52 4-Stroke only to have to add 6 oz of dead weight to the nose to make it balance. Make sure you take the the spinner, prop, muffler and mounting bolts into account when figuring this out!

P.S. In all fairness, I've also had good luck with O.S., Saitos and Thunder Tigers. I believe all manufacturers have some good models/runs and eventually they all also turn out a lemon or two. I try not to get too religious about one brand or another.

That's my $.02