For matrixed surround, it's really only a matter of telling the receiver what to do with the signal. When using a Dolby or DTS encoder, you can specify whether it should interpret the input as an LtRt or regular stereo. It's just a single bit in the metadata being flagged as one or the other—the actual mix doesn't change at all. PCM tracks don't have any flags, so you have to manually choose which mode you want the receiver to play back in. Not a hardship for me, since I tend to switch modes based on what I'm listening to anyway.

Concerning theatrical DTS, I don't mean to potentially throw a wrench in the works, but I just discovered a problem concerning subwoofer crossovers and level calibration, which leads to the mixes not sounding right. Read about it here.