Well, it appears this thread is finally slowing down. I've spent way too much time here reading all the comments and great advice. I'd been salivating over the Mayhems for months. I finally got a hold of one back in August. After an extended build period (fortunately, I didn't track the hours) I have mine ready to maiden. Hopefully this Saturday--if the weather holds. [8D]

Here's how I'm setup:
Magnum 1.20 4-Stroke
APC 16x4W
Hitec HS-645s on the Ailerons
Hitec HS-5625 on the Elevator
Hitec HS-5945 on the Rudder
6.0V, 1800mAh Ni-MH RX Battery
Dry Weight: 8lbs 4oz

If came out a little heavier than I'd hoped, but the Magnum weighs in at almost 32oz and I just couldn't resist the wheel pants or the pilot!

Due entirely to the advise posted in this thread, I moved the rudder servo to the rear early on. I wanted to post pictures of my rudder servo installation, because I was able to get it to the extreme rear of the fuse. It's basically directly behind and in-line with the elevator servo. With a couple small hardwood blocks, it just clears the other side of the fuse! With the servo more towards the rear, the weight is more effective and the linkage is shorter. To pluses in this case. If you setup for the rudder servo BEFORE INSTALLING THE TAIL FEATHERS, you can easily slip a nice sturdy plywood reinforcement plate for the servo hole through the vertical fin slot in the top of the fuse. I was able to lay the fuse on it's side with the rudder servo hole facing up, then slide the plywood plate (top covered with epoxy) through the slot and use two small L-shaped pieces of piano wire to pull it up against the inside of the fuse. Worked like a charm!

Mine balanced a little behind 5.25 with the battery just behind the canopy. In the picture, you can see the receiver wrapped in foam--the battery is installed just behind it under the canopy.

I can't wait to get it in the air!