P2Pool as backup, CGminer?

[mokahless]

I was just wondering what everyone's experience is with CGminer's backup pool settings. I currently have BTCGuild as my primary and deepbit as my backup pool. I experimented with P2Pool for a bit over 24-hours but the payout was < 50% of that of BTCguild. So I have it set now as my backup of my backup pool. Logical, since it won't go down.
I'd like some thoughts on this and backup pools in general but I also have a few questions.
I use CGminer and have these set as my backup pools. I'm not using the --failover-only switch and am wondering if this could be more or less efficient overall in everyone's experience? What do you think a good idea is with regards to this switch?
I also wouldn't mind any thoughts on P2Pool aswell.

Think of this thread as a discussion on the various topics mentioned above.

[-ck]

p2pool is virtually a different block chain. If using it as your backup, you almost certainly will only benefit from it being a backup with --failover-only enabled.