Few things here. Though i haven't had much time to test but this can all be found online:
1) reaver has a feature to stop an attack and continue later (apparently you need to save the session somehow, though it might save itself?)
2) from arstechnica's review on it "The attack took about six hours to properly guess the PIN and return the SSID and password for the target network. During that time, the router locked up once under load, as I was putting normal levels of network traffic through it from other devices. Some routers will also lock out WPS requests for five minutes or so when they detect multiple failed PIN submissions—mine stopped responding occasionally, generating a string of warnings, but Reaver picked back up where it left off once the Linksys started responding again."
3) there is a new version (1.3) which apparently is a little faster (save a few minutes? lol), but it also includes a program called walsh to scan and detect devices which are exploitable - i can't get walsh to find anything on my system... =(
i'll have more time to play with it later but im sure there are still lots of bugs being worked out.
Also, there is another script which is apparently faster then reaver ... (once again, haven't tried it yet...)
good luck and hopefully in the coming days we can figure out things a bit more!
btw, this is my first post and i love hak5 =)