This was Christmas-eve dinner for us this year. Recipe straight out of the BGE cookbook, as posted elsewhere on the forum:
Probably the easiest thing I've cooked on my BGE so far, and I have to say - it might be the best so far as well. It took me a little longer to get the tenderloin up to temp (I was shooting for 155) than the 5 min per side the recipe calls for. This may have been the result of me trying to cook bacon for Christmas morning's breakfast on the egg at the same time.
Anyway, the result was so, so good. Incredibly moist - more than any other tenderloin I've had prepared in any other way. Definitely worth repeating.