I'm glad almost everyone got this plane fly successfull.
Make sure to use correct servos.
I recomending JR DS 3421 metal gear for elevators. Hook up the linkage rod about 3/8" from the center of the servo arm. This isvery important for mechanical advantage. Most flutter incident happen was done too far out from the center of the servo arm.
Crow set up is the way to land the viper jet. Flaps along will not enough to slow down for landing.
3/8" crow. Full flaps. No need to trim elevator if set up the flaps servos to travel slow to deploy the flaps.

Before landing. Slow down the speed. Put out gear first. After it slow enough. Put down flaps and crow. Add little throtle to kept the airplane fly nose high. Not to worry about stalling. With the crow set up. It won't tip stall. Use your throtle to control the decent.
If you got use to it. The Viper Jet can craw in for landing.
Have fun with Viper Jet.
I can't wait to EDF version flying soon.