The 'only' bad is the original Vaquero is 'oversize' for the .357 cartridge. The New Vaquero is back to the frame/cylinder size introduced way back in '55. Both revolvers will take any SAAMI .357 load you can stuff in it. Now finding a load that works 'good' in 'your' gun is up to you. I like shooting 158g SWCs in my .357s. Since this is a fixed sighted revolver, once you find a load that shoots acceptably (say 1 hole at 25 yards would be nice), then time to adjust sight accordingly to shoot to POA. Hopefully it shoots low, so you file that front sight down. If left or right, you really need to have the barrel turned by a gunsmith (or Ruger) unless you want to put up with some kentucky windage. For me, I had access to a gunsmith here for my original and New Vaqueros. He takes his barrel vise to the range and we zero'ed the revolvers out there (shoot, adjust, shoot adjust).
The loads I like to shoot are in the 1000fps to 1100fps range out of a 5 1/2" barrel. I found good loads with Unique, Red Dot, Green Dot, True Blue, CFE Pistol, Universal, 20/28, Bullseye, AA#5, and 2400 (for a warm load) just to name a few. That aught to give you a start. Right now, Green Dot is my preferred powder. 5.5g under 158g SWC, standard CCI primer. Nice comfortable accurate load in my revolver(s). Note, I never use .38 special cases in my .357s. I use .357 cases only across the entire power range.