none of the above. i've been using stihl equipment since before i was in business. i haven't seen a thing on any of them that suck. you could say my only hope in posting how much i love the new caps is that they will see this and not revert to old screw on style. maybe i am lucky because i'm not kidding. i don't use vice grips to remove the cap because its swollen. it's just a little more snug in the hotter temps which doesn't bother me. there is nothing wrong with the screw on caps but i think the new style is quicker to use. i'll keep you posted on that blower. might be a while though. i might forget by that time to post. as long as my br400 keeps kicking it will be around. unless i run into some extra money and can purchase it with no justification. i've purchased enough equipment this season that i'm holding off until i actually need something. although i do know plenty of people with the br600 who haven't had any trouble.