IMO, the .35 kicks a bit less than the .270. A lot has to do with the flash and blast from the .270 due to the slower burning powder having a lot more excess oxidizer that gets consumed as it hits the air.(aka "jet" effect) But, I havent' shot any factory level .35 (or .270) in a long, long time. My .35's tend to run a bit "warmer" than factory loads. Puts a real "thumping" on deer and pigs out to ~200yds. In the s.e.usa, the .35 is as popular as ever or even more so. Can't find the 150gr Remington loads like you used to could, but 200gr Federal, Remington, and Winchester is usually around. If you can order it, it's only a little more expensive than .30/30. But, it should be; more brass, powder and lead..... You really do get what you pay for......
I too suggest that you get a basic reloading kit and learn to reload along with your boys. Kinda like a "merit badge" project with the "Scouts"..... You'll learn somethings about your boys too. Hopefully they won't learn any new "vocabulary" from you in the process....
(had a friends son tell his mom the new "words" he learned from his dad at "scout" camp.... hilarious story, at least the way the "mom" told it....) I digress...
My brother taught his son to reload with the .30/30. First they spent an afternoon casting the bullets with a Lee mould I gave him (.309" 150gr FN). They then lubed them with Lee liquid alox- didn't bother with sizing or gas checks. Not really needed. Next day, they loaded the .30/30 brass they'd previously prepped. They used ~7.5gr of Unique. Loaded a 2lb Coffee can full....
Next day, they went shooting..... After seeing "pop" shoot several, Jr. thought, hey, this is about like the .22.....
Went through 2lb coffee can in the '94 in about 30min...(~200rds!).
Jr said, drats! now we get to go load them again!!!!
Son qualified tops in his company w/M16 and M9 in basic training when he enlisted in National guard MP unit in 1988...... Saw action in Iraq in '91, Again in '03... Recently retired from guard w/20+yrs. Never know what an afternoon with your boys will result in........btw, he was 9yrs old and had no problem with M94......