I want to get everyones general impression of monks (ie: effectiveness, fun factor, whatever else yuo feel like sharing). I was also wondering wether they get to take part in any hold quests?

I've never played a monk but from what I've read on this forum the general opinion seems to be they are excellent at high levels and not so good at lower levels. I think they have the thaco of a cleric as well which sucks. As for the stronghold they get the fighter stronghold, Nalia's keep.

No, its the monks XP table which is like the cleric's, not THAC0 advancement.
And yes, monks get the Fighter hold.
IMHO, monks are great - they are both deadly and interesting, which makes them so fun. Yes, they are pretty weak at low level, but when they reach levels 15 and 16, they become amazing - great THAC0, great AC, great immunities, amazing Magic Resistance - and on top all of this - KONG FU ANIMATION!!

What more can we ask for? ;)

Continuing with monks....
Can a monk dual class? It would be good to dual a monk
to say a kensai or mage at some level. That would lower their AC and give them better THACO no?

Nope, sorry. You cannot dual-class monks, barbarians, sorcerors, paladins, or bards.

-Sazerac

Everything about the Monk:

here

Monks also have amazing speed in the game, and are total killers.

Having gotten a little bored with EQ lately, I reloaded BG2 and after reading here I started a solo monk.

At first it was a little tough, but monks gain power quickly, and as a solo character I also gained exp VERY fast. I had to use the exp cap remover by the end of the 2nd chapter. At level 20 or so when you can no longer be hit by normal weapons the game changes alot. It's fun to walk into a room full of baddies and leave the keyboard to take a 5 min break and come back with no damage done.

I think you max out at 4 hand to hand attacks per round and fists max out at 1-20 damage (considered +3 weapons at level 15). Monks also move fast, gaining a faster movement rate as they advance in levels. And the abilities are very nice. Stunning blow (save vs spell) stuns an opponent letting you beat the tar out of them while taking no damage; and Quivering palm is an insta kill ability (save vs. spell).

Slight spoiler.
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Shadow Dragon - one hit with quivering palm. Dead. I was very impressed.

I love monks. Hate their clothes though.