Last longer. Period.
Yes, if you lose any part of your erection it's very possible, and probably likely. Read the damned directions, it says immediately after you cum to pull the fuck out.
Try taking some maximum strength oragel and putting a bit on your dick before you start. Heheh, sounds strange as hell but it's the exact same chemical that's in the "extended pleasure" condoms.. topical anestetic, benzocaine IIRC.
No, not from personal experience. although I have been known to expirement from time to time... I hear ya about the super-long-lasting girl though.. Makes things a bit harder sometimes.
peace,
-Phil