[Kalium]

I've got a Dell Precision 5510 with supported Ubuntu that's been good to me so far. I had to argue with a keymapping or two, but it's been solid otherwise.

[shaneofalltrad]

I dual boot (on its own ssd) with a Dell Precision m6600 and it is amazing. Only issue is it is a workstation with tons of power, quality built in that makes it a concrete slab on your lap. The power supply is a brick.

[shaneofalltrad]

I also have installed Ubuntu on an old Vaio and that has more than enough power/space and it is comparable to a mac for usability.