It's much MUCH faster overall. Everything is quicker, and force powers are more risky to use (Jump too high and run too fast into a wall and you can DIE).
It's really fun, especially with all the mods and maps out there.
The only thing though is that the Saber combat is VERY SIMPLISTIC compared to JK2/JA. Basically there are 8 swings, but only one is truly useful online, and it can kill in 1-2 hits.
So just imagine a duel where people use the same move over and over again until one of them dies.
It was a ton of fun back in the day since there was nothing like it, but now that we have JA, the saber combat looks very dated.
However that said the rest of the game is masterful and the SP is much more forgiving (the puzzles are more logical and the guns play isn't so unforgivingly frustrating like JK2).
And unlike JK2 and JA, the SP and MP are virtually identical, so the skills you learn in one carry over into the other.
JK1 and MotS are based on the Peer to Peer system rather than Client Server. So no dedicated servers are possible, but that said, the game handles lag fairly well for smaller games (4 players on dialup, 8 on a LAN) and the lag is "more fair" (ie: you keep playing but you just have to lead more and hit people more times to kill them and people with faster connections don't have a huge advantage).
So if you are dead set on re-creating the saber dueling experiences of JK2/JA you won't find them here, but you will find a fun and fast paced game that's well worth playing through.