GJM -- I think you'd find quite a few folks here who'd disagree. For every person I know who shoots a SFA better, I know one who shoots the LEM better. As such, I think it's hard to generalize that one is inherently better.
Furthermore, as with all things, you need to examine the test. Rogers involves a lot of single shot transitions between difficult (distant) targets under time pressure. There are very few requirements for multiple shots on a single target, and when there are it's a huge target. The first shot from the holster is almost always to an equally huge close-range target, and when a ready position start is used it mandates a ready position that makes a proper press-out almost impossible. There is never an instance in which targets need to be ID'd and the entire downrange area is a free fire zone; I've witnessed a substantial number of ADs going downrange between targets at Rogers but there is no penalty except a wasted shot.
Lest anyone think I'm picking on RSS, the same could be said for the F.A.S.T. It puts emphasis on certain things (draw to a low probability target, reload) and ignores others (movement, target id) in a way that certainly fails to represent "average" reality. Obviously I don't think that makes it a bad test just as I don't think the RSS Test is bad. But you need to understand what you're using as a basis when you start relying on its data. Just because a particular gun turns in "the best FAST" or "the best score at Rogers" or "the best score on the Humbler" doesn't make it the best gun.
As others have said, the biggest issue many of us see with the LEM is that folks -- even folks who give it an honest try over months and thousands of rounds -- don't actually learn how to shoot it. It's different. Whether it has an advantage that makes it worth the effort to learn that different is a matter of personal choice. I happen to think the LEM is brilliant but I honestly couldn't care less whether anyone else uses it. What I care about is people making intelligent decisions based on rational factors. There's absolutely no doubt that will result in some people preferring one system, and others preferring another.