Rubber is often not quite as nice as spring.
I prefer non strato. Strato is an EPA thing, not something designed for performance and longevity. The verdict isn’t quite in if you look at these threads but stratos usually turn more RPMs and when mine are even tuned a bit rich, run hotter than my traditional 2 strokes. I also have more trouble tuning my strato(ms261). It just doesn’t respond like I wish it would.
The 501p has an inboard clutch like most pro Husqys and all the Stihls. Most prefer that. I like my saws with outboard clutches. My Husqvarna 395 is as pro as it gets, and runs an outboard clutch.
Adjustable carb is great, but if you’re asking, might not be right for you. Some of us like adjusting carbs. Others don’t know they need adjusting. Not just any ole’ body needs to be messing with a carburetor.
The comparable Husqy would be the 550. I’ve had a couple. They will cost you much more, and offer you hardly anything over the 501p, except marginal performance and a better looking saw. Like I said before, the 501’s are ugly. Crank stuffers? Whatever. I would put my money on the 501p lasting longer just because I think Echo makes a darned durable engines. Husqvarnas are good too though and I’ve always liked them. The rancher series are good saws as well and I’ve enjoyed running them. They are heavy compared to the Echo, built more like homeowner saws (even though I don’t agree with that whole racket), and are still going to cost more.
Sounds like you will remain skeptical about the Echos regardless, so just get a Husqy first, and go from there. Owning one brand will teach you nothing, and reading people’s opinions on this forum about which brand is best might make you stupider. I started with Stihl, and now am mostly interested in Husqvarna and Echo.