After testing a couple of media playing apps, I'm still finding that Azul Media player is by far my first choise. The latest version is really stable and does the job for me. I have 300+ movies in all kinds of formats and it plays them all well.
It has: Passcode lock, Landscape lock while watching a movie, TV Out, I Download videos directly, I share via iTunes File and the file formats that are currently supported are: 3gp, sf, avi, divx, dv, flv, gxf, m2p, m2ts, m2v, m4v, mkv, moov, mov, mp4, mpeg, mpeg1, mpeg2, mpeg4, mpg, mpv, mt2s, mts, mxf, ogm, ogv, ps, qt, rm, rmvb, ts, vob, webm, wm, wmv
And the killer is a really great support. Whatever question I have, I get an answer very fast and you see your tips, wishes etc. in the next updates. Great support is what makes a product stand out.
I would definitely recommend it to anyone that is looking for a robust media player.