TRoT is good because it isn't completely filled with annoying mobs and the hiking isn't quite as bad. Some of the encounters are actually fun and there is decent use of skill checks. There is some way to increase the movement speed in the INI IIRC so be sure to do that. The expansion is considered shit because it goes back to having heavy combat. Honestly, the combat would probably be great if it was just turn based, but instead it's like Ulminati says, a really bad MMO.
FAKE EDIT:
Only drawbacks for me were the combat. RTwP isn't the problem, the problem is that enemies are constantly chasing your mages/archers and there is no attack of opportunity or defense line you can build to block them. Think about Benny Hill style runs. Best is to give even your mages a lot of hp and use them for melee combat and buffing most of the time. Another flaw is that your chars can't die and healing is too easy.
Ahhh yes, but I do consider this a flaw of it being RTwP since that system has never really done attacks of opportunity right or blocking IMO.
If OP plays the first one, avoid that rat dungeon at all costs! It's a lame joke on the developers part and seeing rats rush through your fighters to get at the weaker mages/archers is infuriating.