they are excellent tools but I imagine that like most 'classics', the latest versions may not be of the same build quality
MSR stoves are as good as they always were if not better as the new pump is a lot better than the old ones.
MSR stoves always seem to get knocked for the pump quality and to a degree it's true. But there have been lots of differing pumps for the stoves. I'll explain.
V1 Yellow pump this is the oldest MSR type of pump and is commonly found on really old XGK's or GK stoves or the old Firefly remember those??? It was a really good pump made from yellow plastic and had a aluminium pump rod. If you've got one keep it... It's the best pump MSR ever made which isn't surprising as it predates MSR being bought by Cascade Designs....
V2 Black and Grey all plastic. A more modular pump with a plastic moulded pump plunger. The pump rod is locked into the body with a 2 piece collet arrangement which uses bayonet style locking lugs these can fail and make the pump U/S but generally it is pretty solid just dont pump to enthusiastically.
V3 Red / Grey plastic.... Nasty and cheap often prone to failure around the neck of the pump where it screws into the fuel bottle...
V4 Red / Blue Plastic Nasty Same as above
V5 Duraseal pump as fitted to the latest stoves. Very good pump far better quality can be retrofitted to all of the older stoves just get the right version for your stove 1 (Red Grey) fits all MSR stoves except the Dragonfly the other ( all Red) fits the Dragonfly only...
I actually like MSR stoves and have used quite a few models over the years and have an original XGK and a GK and I think there is a Whisperlite somewhere also. They are great but pretty poor at simmering which isn't surprising as they're really designed to melt snow for water at high altitude not knock up a bachmel sauce without lumps... All roarer burner stoves Primus Omnifuel , Optimus Novas etc are also very loud... In an 'F111 on full after burner' way.. Which can get tiresome...