They make trimmers for stretched necks.
Like most cases, brass life depends on how hard your running your loads. The 22 hornet is particularly sensitive in this regard due to it's already thin brass. If your squeezing everything out of it trying to make your hornet into a 222 then your going to get 3 to 4 out of them before they give up the go. When kept mild and well within reason I've gotten twice that from them. 5 to 6 isnt bad either, sometime you take what you can get.
You can pretty much tell those that havn't had much success with the hornet. They complain about accuracy and brass life. Generally.. those are the guys that are wanting more than the little cartridge can give. If a person takes the hornet for what it is, they will enjoy a lifetime of shooting with it.