Not sure what experience your friends have with small gassers that would lead them to make those statements. True, power to weight ratios of most large glow engines will exceed that of most small gassers but the drawbacks of glow power in the 1.20 and up catagory pretty much even the playing field. Also, as far as single cylinder gassers go for the most part the bigger they are the more vibration they tend to have. I've had great results with 26cc engines in scale aerobatic aircraft up to 78" wing span and 12-1/2 pounds. If 3-D is your bag you will want to keep the weight down to around 10 pounds. Many 1.20-1.50 sized aircraft can fit in this category. As far as choices, there are many, Zenoha, CRRC, SPE, XYZ, RCGF, to name a few. Search the threads, there is no shortage of opinions, or reviews on all of them. I do reccomend that you contact a US based dealer and talk to them before you buy, they will be your source for post purchase support down the road.

Jody