They both play out the story of Niko from Luis and whats his name biker guy's point of view. I haven't played through the biker one, but Gay Tony was fun. Both are probably about 1/2-3/4 the length of GTAIV, but I think I liked Gay Tony more than IV. The engine is slightly updated and on my system the game ran at roughly 10fps faster than IV which was a nice extra. If you liked IV, you should like these.