My favourite poker variants is Horse, 8-Game, Omaha H/L, Stud H/L, the reason is that with hight and low and the change of games, it keeps my mind very busy with DECISIONS, DECISIONS, DECISIONS, and I love it. Instead of thinking Oh! no not this again, same old thing.
That is why I really like PokerStars the best and also their format.
Of course, all of these poker rooms are programmed. Not rigged. And sometimes I wonder if the programmer had a lot of fun in programming the AA losing to 22 even though the AA hit a set on the flop and then the 4th street hits a flush draw and I win on the river with a flush my 22..