I use Viki most. I was with KoreaOnDemand for a few years but as you say, Viki was faster with subtitles. KOD did have some different movies, but not enough to make it worth while paying for both...
I was looking at a Chinese site, iqiyi.com, and did the one month signup, but I couldn’t figure out the search. If you ever DID get to the video, it was wonderfully convenient with all the episodes dotted to the right when you weren’t in full screen mode.
But I also like viki.com’s pages on actors. With actors like Song Joong Ki, I keep checking for other dramas he’s in. He was compelling in Sungkyunkwan Scandal and in Descendants of the Sun.