Somewhere on here there are weights of a 241,421 and 543 and they are all right there with each other. The dolmar wasn't the heaviest either! Plus in my experience they are right there with the 241 in terms of power.
Did someone summon the chainsaw weight genie?
The 543 is very light, but the build quality is also very light...if you know wot I meen.
The Dolmar is a pro build quality. I have one that's been in firewood duty for 5 years, that I've ported, and it's not missed a step. I would highly recommend the 4300/420/421, especially ported.
The 241 is also an excellent choice. It cost quite a bit more than the dolly, but it does have a much larger carb that responds well to porting. It's MTronic, tho - which I admit I am not fond of.
This Echo/Shindaiwa 390ES is an alternative if you can find it, but they are not what I would call a limbing saw. These make stock Dolmars seem like 346xp's. They are slow revvers, but have a lot of pull at about 10k rpm. We had one I muff-modded for the estate I work on that was stolen. And, quite frankly, I think they stole the right saw. I prefer most other 40cc saws to it. Still, a nice handy saw, if not cheap like the 50cc Echo's are. This pic is with the cat in it - the cat weighs about 4-5 ounces. So it is super light for a pro build
One thing to consider is most saws that are very lightweight achieve this by having lightweight AV - usually hard rubber(as you can see in the photo above). The Dolmar and Stihl 40cc offerings are spring AV.