I'd probably go with the 7mm mag.
I used to be a .25 fan. I lost a good buck well hit with a .25-'06. I found the carcass a few days later still intact enough to determine entry/exit points. It should have been DRT, or within 40-50 yards anyway, it should not have gone full-steam over a ridge 400 yards away. I lost a lot of confidence in the smaller calibers right there.
Tom
Sounds like you had insufficient bullet performance, not an insufficient cartridge!
