I am mostly electric so can't advise on gas vs. glow but a lot of .40 class planes are being converted to electric. I did a survey a while ago and it seemed anything under 10 pounds was going electric. Over 10 pounds was going gas. Glow, while still in use, is very much on the decline.
As for radio, I presume that 7C is on 72 MHz. It is still legal. Very few people are flying on 72 MHz so you should not have to fight anyone for the frequency BUT, now that 2.4 rules the RC airwaves, frequency control as almost completely gone away so make sure that people know you are on 72 MHz because the next guy on 72 is likely to assume no one else is on 72 and might be on your frequency. Watch for those long antenna and get to know who is still using 72. Likely people are not checking the frequency board.
Last edited by aeajr; 07-24-2018 at 08:10 AM.