RE: Twin Trainer
John,
I have been flying twins for a while and I would reccomend two ARF's. Both would use OS 46AX's as they are strong and ultra reliable.
The first is the Cedar Hobbies Twin Stik. It's cheap and very forgiving. Not much to look at and prone to flutter, but properly built, it's pretty foolproof like all Stiks. Downside is the lack of fuse between the engines which is hazardous for starting...stay on you toes.
Second is the Seagull Dual Ace balanced at 100mm. This is one of my favorites and a good aerobatic, clean and honest airframe. Needs longer nose gear such as a Falts and larger wheels. This month's Model Aviation has a review. RCM did one a while back with Dick Petit.
I've also had several Duellists kits and now have Cox's ARF. While a wonderful airframe, it is not a good first twin.
Stay away from the P-38 and other scale models until you have a feel for syncing twins, etc.
Good luck....
Bo