It would depend on the condition of the MSFL (Buying used can be a crapshoot), and the quality of the re-mastering job done on the 180 gram. I've heard 180 gram re-masters that are better than the original's, but MSFL in mint condition is hard to beat. The thing is, is it really in mint condition. I don't buy a lot of used vinyl anymore, as I've been dissapointed in what some folks claim to be mint condition.
John
John