I have an EPYC 7351P (Zen, like 1st gen Ryzen) server. Their Achilles heel is communication across dies making it much more affected by slow memory than their Intel counterparts. They're also an order of magnitude cheaper and the single-core performance difference is completely negligible. It's a little slower in some aspects and a lot faster in others. For example it's a little slower when scheduling SSE instructions but a lot faster at scheduling AES-NI instruction (presumably because per-VM RAM encryption is one of the features it boasts).
It's a much faster CPU than Intel will sell you for anything approaching that price, but it's no good for HPC stuff if you're into that sort of thing; or for that matter anything else that requires a lot of synchronization across a lot of cores.
It's hard to compare temps because I have an entirely different cooling setup than Intel machines it replaced however it seems about proportional to Intel machines in terms of power/performance. I'm not blown away by low temps but it's definitely not running hot. Even at full load it can barely make the firmware (which here maintains a constant 50°C temp on the die) spin up the fans. These things are supposed to be usable in 1U cabinets after all. Power draw has also been pleasantly low.
Fuck the SP3 socket though, holy shit. My first board came with an almost invisibly bent pin and the result was months of trying to figure out why the fuck the RAID controller kept getting disconnected about a random amount of seconds after or into POST. Had to get an angled fucking zoom shot just to see it. Since it comes with its own cooler mounting holes, which under normal circumstances I'd consider great, and since it's the same size as TR4, you'd think you could use any Threadripper workstation cooler but nope, fuck you. It's a very elongated rectangle and 90° rotated from each other so they're basically incompatible, unless you're not bothered by unnecessarily poor cooling performance.
Ryzen thankfully uses a saner socket. They somehow managed to make pins on the CPU seem preferable.
With all that said, it's undoubtedly the best computer purchase I've ever made.