Personally, I find Andermatt one of the best resorts I have ever been to, with reasonable prices for S/R and lots of on/off piste possibilities. I skied in Sedrun/Oberalp only once but it did not give me much thrill despite epic train ride with Matterhornbahnen. I like going there during week days when there're less people and I can get to Gemstock more often than not. Not only black/red runs but also free-ride area with huge moguls is my kind of thing. However I won't turn down any weekends offers even if I will mange to use the cable car only once or twice. The only thing that I dislike is the infractructure of the first lift. I hate the long walk, it could have been situated closer to the main train station.