As a setting Faerûn can be a bit of a marmite setting. The diehard Gygax followers have never accepted it. Greyhawk adherents never needed it and it seems that with every new edition of D&D they feel the need to reinvent it. So why bother with Rolemaster and Faerûn?
I will not deny that Faerûn is not perfect. The original (grey box) edition barely sketched out the world as a setting for half a dozen modules and we were kind of teased into it by Elminster articles in Dragon magazine. After then there were so many seismic shifts that it is hard to keep track of it, gods dying, Mongolian hordes and volcanic eruptions not withstanding. Another criticism leveled at the Forgotten Realms setting is the über powerfull NPCs such as Elminster and Drizzt Do’Urden.
I, like many other roleplayers, cut my teeth in the D&D world, Greyhawk in my case, but then moved on to other games and other worlds. Last year I started to plan a new campaign after not GMing for a few years and I offered my players the option of a D&D game just for old times sake and I was surprised at the negative reaction. Despite that the D&D game had moved on generations since we last played no one was interested. We have always been dedicated Rolemaster players and that is what they wanted.
Setting a rolemaster game in Faerûn is pretty easy. Creatures and Treasures (I, II and III) cover 90% of all the creatures you will ever need. There are very simple rules included in C&T I to convert any that are not there over to Rolemaster and you are 50% of the way there. The other 50% is the NPCs.
There are numerous excel based spreadsheet type character sheets to help speed up character creation and my favourite piece of software (Rolemaster Charactder Utility) makes creating a middle to high level character the an hours work. This is where you can decide if you want and all powerful Elminster or not.
If you have a party of experienced D&D players then having a go at Rolemaster, even with a fairly simple adventure will be an eye opener (in a good way I hope)!
I am a RM2/RMC (Rolemaster 2nd Edition and Rolemaster Classic) player but there are other flavours available including a freebie 3000L_HarpLite (High Adventure RolePlaying) which has everything you need to get playing.
Why not give it a go?