Rule also makes a pump real similar to the NRS that you can find for about $60. One of my friends bought one last year and it's holding up as well as any LVM pumps he's had. He only uses it for a small cat and an IK so I don't think it gets the workout it would blowing up a raft.
I got to use a friends Blast pump the other day...it's surprisingly efficient, however it does heat up...a lot. There is a small hole in the exhaust tube that you need to cover with your finger to get any sort of real pressure from it and the air passing by my fingertip was way above warm. Good little unit, especially if it's not too expensive.
The LVM you can buy every part in it as a separate piece so if any part of it ever fails you can rebuild it. I don't see any parts listed for the Blast which means if it dies you probably have to buy a new one. I've had to resoldier my switch a couple time on the LVM but other than that it's a great little pump.