The Masters is easier to cash in, and get some return on your bowling investment. The US Open is closer to you and would be less money in travel, hotel expenses. The US Open will be harder to cash in, and a true bowling challenge.
Depending on how much money you have to spend, bowling the US Open will at least save you air fare.
Both are going to be tougher conditions, but historically the Masters has been the easier of the two tournaments to make some money at.