I've got one I've had for a long time, X-Rite i1Display Pro. It still works and I use it on all my home/work computers. I am curious about what the current best options are as well.
Calibrite Profiler software with the calibrite Display Pro HL.
My old (now in storage) X-Rite DTP-94 Colorimeter was awesome but sadly Integrated Color stopped supporting the software when they went out of business.
Calibrite Display Plus HL. The Pro HL would be more than enough for my current screens. The Plus seemed more "future proof" for whatever my next monitors and TVs might look like.
The first couple versions of the Profiler app were buggy. But the current version has been working well. Well, I just updated to the latest software version 3.1.0 and found a bug when trying use a second display. Ugh.
X-Rite i1Display Pro that's now so old the plasticizer has started seeping and made the plastic parts all sticky But it still works well with the Spectraview software on my NEC monitor so I'll keep using it.
I did buy a SpiderX Elite last year that was on some insane sale but have yet to use it.
ColorMunki Photo here. It's cool as you also can use it for making printer profiles. Get a second hand for cheap and download ccStudio (free).
It won't work together with HDR monitors though
But it still works well with the Spectraview software on my NEC monitor so I'll keep using it.