I am sinning a Dell 15 7000 series (7567) and it does an amazing job. It is a decent budget gaming machine with 16GB of memory, a discrete graphics card, and a backlit keyboard. I will bring the memory up to 32GB soon, and maybe even get a better screen. As it came from the factory it needed a bit of tweaking of the color settings, it comes pumped way up. I am running it on Ultra and it performs really well.
I think any of the Dell 7000 gaming series would work well for SL. Unless you want to spend a fortune on a super high end gaming machine, this is a good solid machine that will run SL for a while to come (my last laptop lasted 7 years before it became too slow sluggish). Get the best you can afford.