sling is probably best option. get an hd antennae for your TV's so you get the local channels....
as for devices, Roku and Amazon fire stick are probably the two best. i like Roku because it comes pre loaded with Amazon Prime, and you can down load apps at your leisure...not all devices will let you download all apps....so ask about that if you want access to more than just waht that device may allow.
of course, if you know somebody, you can get hacked amazon firesticks and have everything you ever wanted.
Maybe in these 14 pages, there's discussion about performance. Skimmed, didn't see it. I've been all Youtube TV for a couple years. Before that, I tried them all and had issues with all of them (Sling, DirectTV Now, Hulu Live). I especially wanted to like Hulu Live, but it just didn't look good to me (especially live sports) and would buffer some. I never have issues with Youtube TV and it looks amazing. Is this consistent with other's experience?