Your new model vaquero is safe with any SAAMI spec load. Many people who handload will tell you that they are actually safe to 45acp levels, which is higher than 45 colt. I believe this to be true, myself, and see no reason to suspect it isnt. The gun is offered in a convertible so the frame isnt any issue, they are both 45 holes in the cylinder, so it shouldnt be an issue.
With that said, if it were me, stick to the loads you were shooting in your colt and be happy. If you want to hotrod get an Old model vaquero or a blackhawk.