Originally Posted by ftrichard

I'd edit your post to say the Marriott Merlin Beach ;-).

In any case, to answer your question... I've stayed twice at LeM before the Great Plague and just returned from five days at the Marriott MB. I wouldn't stay at LeM again. It's a fine property but I've never had a meaningful upgrade there and I didn't feel they cared much about elites. At the Marriott we were greeted by the Director of Rooms, given a Chang beer at check in, upgraded to an ocean-view suite, given two drinks vouchers, and invited to a Bonvoy elites drinks event on the Wednesday. So we've had a better room and better experience at the Marriott. Just my feeling based on recent experience. YMMV.

Both properties have effectively their own private beaches in their own coves and have good breakfast spreads. The Marriott is slightly closer to and has a free shuttle for the short journey into Patong if you want to go shopping or visit other restaurants. It is also more family orientated with plenty of activities and a play area for younger children. It's got lots of F&B outlets if you want variety: a sports bar serving burgers, an Italian restaurant, a Thai restaurant (quite decent), the main buffet, a beach grill, and a beach bar. Each night there's a different themed all-you-can-eat buffet. Remember I've just got back from there so I have a better recollection of these facilities. I'm not saying the F&B is better than LeM, just that there's a lot of variety which I do not recall from LeM.

Definitely, with such a price discrepancy, I would personally choose the Marriott based on my last stay. Even if they were the same price. But, as ever, personal preference and evaluation of value do have an impact.