if you ever go w/a bigger & wider tire & actually need 15x10's..Stockton wheel can widen the 15x8's to 10'', but w/a 12.50 tire i would use the 15x8's, & if your tires are 11.50, definitely go w/the 15x8's
I'm running my 18.50'' wide 44's on 15x10's & they don't look to bad...a 15x12 would probably would look a little better but i bought these tires cheap used(50% tread for $400, that's the price of 1 new 44) and i got the 15x10's cheap from summit in bare steel w/2.5'' bs so they would fit my d60f w/o any grinding,..then had them powder coated..
i have to run a pretty low pressure in the tires so they don't crown real bad on the narrow 10'' wide wheels. after these tires wear gone & i have to buy new tires i plan on stepping up to some 17'' or 18'' aluminum wheels w/4'' bs, the rim size depending on what is offered in the tires i get...probally new 44'' TSL's or possibly 49'' IROK's and i think they make them for 17's, but i don't think they are available for a 18'' wheel....yet.