Choosing a good capture card

As the title says i'm looking at choosing a good capture card for myself to stream my ps4(and wii u and whenever i get an xboxone it will be that too and maybe older systems if possible) i use obs studio to stream to twitch here and i am wanting to be able to have it so i can have my controller unplugged. i have used ps remote play but i discovered i couldn't stream ps now games that way. my computer gets really bogged down if i try to use the ps now app so im wanting a capture card that would allow me to capture the ps4 stuff while im playing ps now if thats possible. i also want to use it this way because you cant stream ps now games through the built in stuff and i have my own overlays i spent a long time creating. i would also be using the capture on my pc to play it cause i only have 1 monitor and i use it for my pc and my ps4 since it has hdmi capability so having a low latenccy would be important too. Hope all this makes sense and i hope some one could suggest something i would love to use bestbuy.ca (i am in Canada so it would be nice if its in store but if i have to order it at least ill get a good warenty compared to trying to get it through somewhere like amazon)