Hanes tees show off my guns better than most unfitted tees do so I have a ton. Grey will be a good switch up for undershirt and probably look cleaner. I have a big chest and lats so they are a little tight there so if its pure comfort and you have a big upper body go XL. 15 inch pipes look great in L, any bigger Id go XL too. Id also like maybe 1-2 more inches in length but not a huge deal.