After my opinion 242 is one of the best chainsaws ever made, totally unique.
You can't get a 242 to work like one 550 do, but you can remove the gasket, new piston ring and MM, and it wake up pretty good with those easy modd.
My 242 out run 346oe after those modds, so I ported the 346oe.
242 is a perfect limbing machine, I use it for what it is worth, setup is 325 13" bar, while it can't competite against ported 346oe and 550 with mm in power, those two saws can't competite against the body shape, handling, balance to the 242. Sadly, those things are over seen when we discuss a chainsaw.
Fix your 242, modd it, and keep it Dave, you wont regret, I'll see if I can get a full XPG pack for you this spring, if so those parts go straight over to you, would love to see you with a 242 XPG
550 itself is also unique, without any doubt the best 50cc, another thing we rarely we bring into discussion 550 vs 346 NE is the balance between them, my JRed 2153 and 2253 have different balance, 2153 like 2" longer bar compared to 2253 in balance point.
Do MM on 550 and you have a lightweight monster in your hands, my MM 2253 always make me smile.