I pay 3% at BTC Guild. I get paid for orphans, I get merged mining with NMC (impossible on p2pool solo), extremely low variance, 0.2% stales, and transaction fees.
You're going to have a hard time convincing me p2pool is better than that.
M
I pay what I want to forrestv.
P2Pool has a negligible amount of orphans (didn't even find one in the last 200 known p2pool blocks).
I get merged mining with NMC, IXC, DVC (and could add any other merge-able coin I deem worth it).
Variance is only a problem if you don't earn much on p2pool (maybe then it doesn't really matter where you mine). You can actually verify this with merged mined coins: they work OK but as it's solo mining variance is really high and NMC blocks are a rare but nice bonus.
Stales % doesn't matter on p2pool only efficiency and I'm at 100+%.
p2pool pays transaction fees.
And I run it on a DSL line...
I only use centralized pools as backups and really don't see how I would benefit from switching to any of them. Even if I had a whole week of downtime right now on p2pool I still would have earned more than on any theoretical 100% up centralized pool (which actually have downtime when they are DoSed).
By the way, look at the current IXC and DVC difficulty (43% and 64% of BTC difficulty). This means that at least 40% of the miners are merge-mining IXC and 60% are merge-mining DVC (I'm pretty sure nobody is mining these coins expecting a profit unless they are using merge-mining).
Do you think these miners are aware they do mine IXC and/or DVC and get the relevant income?
No : they are mined by centralized pools and most keep the income for themselves and AFAIK don't even tell their miners about it. When you use p2pool you can at least fully control what your hash power is used for.