@Stephen – Hmmm, maybe… But has your (or anyone else’s) experience included things like the middle of a mosh pit? As I am a HUGE fan of live music, and when my knees are working correctly I like a bit of a shove around – I don;t think it would be great to have a needle in me while I was doing that! And changing around between pump and pens I can imagine being a pain in the arse, especially if it’s at least once a month… I dunno, I don’t really care enough atm – which is bad news for my bloods, but there we go, I’ll perk up in spring I’m sure 
/ rant/moan/whinge