I JUST finished the damn Three Leaf Clover mission in GTA4, on what I think was my 4th try.
Jesus god what an annoying mission.
SPOILERS IF YOU HAVE NOT DONE THIS MISSION AND REACHED THE THIRD ISLAND YET. STOP READY SPOILER MCSPOILERY PANTS.
The cop shootout I'm ok with...it's well paced and they made it far by making you fight phases of cops rather than having to actually do battle with the entire police force just to get to the subway, which they could have done just to be dicks. But fuck the last half of the mission with a rusty nail. That was just cheap to have to make you try and get away from three times the normal amount of cop cars on the road. It took me nearly 20 minutes of driving around before I was able to lose the wanted level. Every time I got 2 feet past the wanted zone, gee what do you know, 8 cop cars from out of nowhere coming right for me on a route I can't possibly avoid them on and they hadn't shown up on my radar until a millisecond before I crossed out of the wanted zone.
I'm cool with challenging stuff, but not CHEAP stuff. And I wish gaming developers were sort of on that page. I don't want things to be easy, and there's plenty of missions I've fucked up in GTA4 so far and had to retry, but I always felt like each time it was just because I did something wrong or just needed to be more careful, whatever.
So I guess if I have an official gripe about GTA4, it's that it was bullocks to make a mission that long with no "mid point" where you could re-start. No, it's not realistic, but I don't care and I doubt most people would.
Anyway, here's a picture of a cat.
Also, of course you're going to have an ass-load of cops, since you did just rob a bank.
I've noticed that it can be a bit inconsistent however, as sometimes escaping (even from 4 stars) can be far too easy, whilst other times its near on impossible.
Ah well, guess its just how it goes.
The only mission that really pissed me off was the final one (more specifically the inconveniently placed crap on the beach). Took me multiple tries before I beat it and the ending was SO not worth it.
Boom.
/facepalm
My only advice for people who have yet to complete the mission is this:
Stay away from your two accomplices during the shootouts or they'll shoot the crap out of you.
When you get past that and to the point where you get out on the streets with a car, DO NOT leave the island..the middle island is the only place you stand a chance of losing the cops because it's so big. Drive around forever and hopefully it'll work out for you. Drive carefully and make your car last. You can try for a paint and spray, but I seriously doubt that's humanly possible to do with the amount of cops out there.
Also, I'm not sure about the RPGs. It might have been grenades that I constantly kept blowing shit up with. I still had the whole lot from that one Playboy X mission with the union leaders.