I would up it to a 310, as that has by far the best AV of the lot. I have had many of the 1127 series saws. The 310 and 390 have larger carbs than the 029 and the 290 though. So maybe sticking with the 290 would be easier. The clamshells can be more of a PITA to rebuild, compared to the pro saws. I would get (and have gotten) a whole OEM engine block to replace it and swap it in. Looks like there are several 290 complete used Mahle engines on Ebay for $75 or so. I would go that route, as I have on the 1127 and 1123 series saws. Mahle is way way better than anything Chicom. You have to pull the flywheel and clutch to pull the engine from these saws. Remember that the clutch is reverse threaded. And you need a small puller to get the flywheel off.