Got Rusty Hearts and not played it once on my Vista box. I have to be honest, for a good three or so months I kept calling it Busty Hearts. Tera Online I've heard of, but not gave it a try yet. My problem is that I program under Linux and live under it pretty much so I don't play many games due to it being my laptop. Its an old laptop that I'm pretty sure wouldn't run anything in wine. About the only thing I play is Minecraft on my laptop and even it lags bad.
The last MMO I played was Final Fantasy XI (which I'm thinking about picking it back up again since they are still developing expansions for it).
I used to play Tera a lot and it is actually a very good game. The combat is very unique in that you actually have to aim all your attacks and not just auto attack and press 1-10 or whatever. You also have to evade others attacks.
Overall it was a very good game. The reasons I quit were these, the endgame content was very boring and repetitive. You basically have 2 dungeons that you run each on a 6 hours cool down timer. They are 5 man dungeons so they are not raids. So once you max level and hit a certain point gear wise all you have to do is run one of the 2 dungeons or farm for gold to restock on crystals, pots, ect. for your next run. I am not sure if they have fixed this yet by adding more end game content.
Another reason I quit was the lack of PVP. They labeled it as a pvp game but in truth when it first came out the PVP sucked bad. The only pvp there was was open world pvp and duels that can range from 1-10 people on each team. They were both good pvp but there just wasn't enough of it to satisfy people. You could look for hours and not find a good duel or anyone to even pvp against. Now I believe they probably solved this by them adding in the ranked and un ranked arena's they were planning but I am not sure.
But overall it is a very good game that I would recommend to anyone that is looking for something different where you don't just press 184.108.40.206.5 in repetitive order to take down a boss or mob.