Hi Dave,
When I was still new to this great hobby I got my first semi scale plane, a Spitfire.
I asked one of the guys that tought me to fly to test fly it. I had also purchased a new computer radio, this was back in the early 90's.
Unfortunately the Tx had an intermittent fault on power and it switched off while the model was in the air. About 20 seconds before I was to get the Tx, as it happened. I watched the pilot hold the elevator sitck fully back as the model fell from the sky.
Now I always test my own models, and other peoples, and even though I only took up helis last August, I have just test flown (successfully) the first heli I built myself.
Unless you have control reversal, or a CG in the wrong place, of control throws way off those recommended, things SHOULD be OK.
Please apply a heafty amount of SOD's law to that last sentence.
I have around 17 years experience to fall back on, but the way I look at it is this, My plane, my money, then I am sure going to be the person to fly it, even if that is only for 2 seconds.

If you are going to test your own model then if possible do it at a time when your club is quiet, and take your time. Even go so far as asking the others to give you some space and time to pre flight it so you can concentrate. They will understand. I built a prop driven F15 once, I had a servo on each elevator, and each aileron. I had mixes set up for flapperons. Took ages to programme. In pre flight at the field I spotted I had the ailerons reversed. ALWAYS preflight the model with no one distracting you with well intended questions. That is when you miss silly things and bin a test flight.

Good luck