Should be torn between 4!
The Sparrow is the easiest to take apart and no tools needed , is a slight hair shorter,can handle 5.7 round and costs less . It also quieter on rifles but has a (annoying to me) FRP on pistols. It can go a long time without the need cleaning.
I have to use the pusher tool when the Element gets dirty but I clean it at home anyways. It's lighter and very consistent can first shot to last, very quiet and hard to beat on pistols for it's size. (excluding Grande cans here)
Can't say for the Sparrow on this but the Element is very accurate with almost zero POI shift on the many host I use it for. This my favorite little pistol can.
If you can only have one and shoot rifles I would buy the Sparrow.
Also consider the Companies. AAC has now fired two good people (who cared) and is owned by a corp that only care about money. Silencerco/SWR seems to mostly care about their Silencers and has great service and seem to have the most fun doing so.
(I like this in a company)
If you wanted even more choices, The new (2012) SWR Spectre Is looking really good (inside) at a good price. The Liberty TL is also an awesome can in your price range. Surefire still stumbling to get their 22 cans out so watch the shot show next week.
Probably 4 good budget cans to talk about too. Its a buyer market for 22 cans right now.
Hope this helps, took me much time to write and correct!