I've heard blue thunder isn't that hot, tbh, but most fuels are ok with the right glo plug. Many engines have preferences of combinations of glo plug and fuel. Get the best quality fuel you can afford. By the way, changing brand later is not a problem (even changing percentage, but that's another thing, there are things you need to do when you do this), but in either case, a retune of the engine would definitely be needed, due to different oil percentages, etc. etc.