Panasonic DMP-BDT120 here. Happily streams DLNA stylee across the network from a Win 7 PC. Little bit of patching needed to get MKV out of the Windows PC, but that wasn't the Blu-ray players problem.
There is no option to connect directly to a Windows Share using SAMBA. But the DLNA option does let you walk through folders so works just as well. Plenty of alternate DLNA servers out there if you don't have Win7 to hand.
Assuming m2ts are just mpeg2 files, then I have played those back without trouble.
My Onkyo is an old TX-SR806 so I can't handle DTS-HD, but instead I use the digital audio out of the Bluray to pass Bitstreamed DTS to the amp with the HDMI connected to the screen.
For me the cost was zero for the player as it was thrown in as a freebie with the screen. Currently retailing at RS for £120. Also has iPlayer, Viera Connect and a handful of internet channels. USB Port and SD Card slot on the front for playback from USB HD\Flash drives. Oh yeah - and 3D.