Usually 4 out, sometimes 3 out, sometimes I put it on hold for a month (if I'm out of the country, for example). For me there are always plenty of BD movies at the top of my queue and (for good or bad) I tend to push BDs to the top even if there's a movie I'd rather see more (with the expectation that it will come out on BD eventually).
I'll pay. At my current consumption rate, my movies will cost me about $2.50 a piece (even lower [$1.75] when I factor in IW) with the BD increase, and I very rarely ever encounter any kind of wait... even on blu-rays.
I'll pay the extra, but if the long waits don't stop or if I continue to have to wait longer than 2 months to get 1 movie then I'm going to stop. Really I've had one movie at the top of my Q for over 2 months and to me this isn't acceptable. I have recieved a few BR disks, but figured out when I have to send a movie back in order to get them. If it wasn't for my planning I'd have a wait on all the disks.