THE LOST AND DAMNED:
-Fun missions, not too difficult*
-New vehicles, including two new 4 wheeled vehicles, and three or four new bikes
-Speaking of bikes, the bike physics have been edited to make them easier to ride
-New weapons, three shotguns (assault, combat and sawn-off), pipe bombs, and a grenade launcher!
-The new Gang Wars are a perfect way to get into gargantuan shoot-outs
-The story is okay, but it's nothing to rave about
-The Gang Wars get pretty difficult when you start to deal with the Mafia
-It's kind of hard to amass a lot of money
THE BALLAD OF GAY TONY:
-Over-the-top missions that are a ton of fun to play
-New vehicles, including a GTA-ized version of the Ford GT, a new 60's muscle car that has a body which vaguely resembles that of a late 60's Ford Mustang, two new sport bikes, and, IMO, one of the best vehicles across all three games, the Buzzard, a compact helicopter that packs a helluva punch with two mounted mini-guns and two mounted rocket launchers
-Parachutes return to the GTA series, adding to the already lengthy list of things to do
-Tons of sick new weapons, including a new pistol, the .357, a new sniper rifle, the always fun sticky bombs, and two new SMGs, one that isn't really practical (you can't use it in cars), and a 300 karat surprise (I won't spoil it for you :D)
-You're associates with "Gay" Tony Prince, the owner of the two hottest night clubs in Liberty City, which means you have V.I.P. access to both his clubs, Hercules, and Maissonette 9, at both clubs you can dance and get as drunk as Barney Gumble, and at Maissonette 9, you can manage the club, have wine drinking contests, and, er, build a "relationship" between you and the other club manager
-The Drug Wars are pretty fun*
-L.C. Cage Fighter is fun to compete in, and betting on fights is an easy way to rack up boat loads of money
-A few of the missions are pretty hard
-L.C. Cage Fighter gets ridiculously hard when the other competitors start attacking you with weapons while the only two weapons you have are your own two fists
All in all, this is an amazing collection, far more than just a couple of expansion packs, I highly recommend this game to anyone who likes a solid mix of shooter elements, driving elements, and adventure elements all rolled into one.
*I've handicapped the difficulty of the missions because I use cheats, you play your way, I play mine.