I saw HST 124+p listed at miragetechnologies.net... for $18/50rd box !!!!
As far as chicks go, i agree with chooch. For 9mm, i think some of the better +P can give you performance just a little under some of the 357sig loadings. If your gun can handle it (and the m&p can) i tend to think +p is a good idea in 9mm, maybe not always necessary with today's bullets, but if i can push a 124gr at or close to 1300fps then that's close enough to the old 357mag 125jhp for me.
I certainly don't feel undergunned, especially with 18 rounds.