If you mean that MERP -system as such - and not the ICE's ready-made adventures - I'd say it served it's purpose and provided hours after hours of fun.
It was our first actual step into roleplaying and we played many memorable sessions with it - changing into the Rolemaster rules little by little.
One could make complaints about the characters and abilities etc. not being true to a Tolkien universe, but then again who says you have to use all the possibilities a game might offer you? And I think that goes to any game: use them as you wish or see fit to what you think is reasonable (no, I'm not suggesting you come up with new rules as how a Rook moves in Chess but I think you get what I mean
).
Haven't played it in ages but I remember it with warmth, whatever the shortcomings were.
The question of how much should roleplaying be throwing dices and looking for the results from tables and how much it should be more free'er interaction is another topic and I'm not commenting on that here.