/scratching head/
Do you mean the 345? Or the 346XP? Those are two
very different saws.
The
345 is a homeowner grade 40cc saw. It's a great little saw - I picked one up from Lowes at a steal of a price in a damaged box a couple of years ago. I've been very impressed with it. For a small saw, it's amazing what it will do. It's my backup, light duty saw.
The 346XP is a discontinued professional grade 50 cc saw. That's a proper general purpose firewood saw.
While the 435 is impressive,and I know Husqvarna says you can run 18", you are asking too much of a 40 cc saw to run it with 18" and as a main firewood saw. It just doesn't have the beef to handle that for long. Yes, you can do it, but you'll burn it up long before it's normal useful life. It's a light duty, trimming saw, not a firewood saw. It's like hauling a big loaded trailer with an F-150 and a little V6 engine. Yeah, you can get down the road, but you won't get much life out of it. It's just not up to the task for very long. People do it, and then complain about how the thing falls apart in a few years.
Because of the less-than-ethical practices of some of the lesser saw manufacturers (Poulan, I'm looking at you) using longer bar length as a marketing ploy to suck in the ignorant, even Husq is getting into the bar length arms race. It's not a good thing.
You really shouldn't go over 16" on a 40 cc saw, or 18 on a 50cc. That USED to be Husky's recommendation, but they are more interested in markets share than quality these days, to keep Wall Street happy. They are still good, but they are sliding. They are not run by the dedicated saw people like they used to be.