R620 isn't a bad system. Its not overly loud for a 1U and if someone is limited on space and wants some density it's not a bad choice for homelab situations where speed isn't necessarily a big factor. As noted above, DDR3 RDIMMs are cheap (I have an R620 & bumped mine & another machine up quite a bit recently at ~$25 per 128GB). CPUs are cheap too. So, someone starting out can get a system with a ton of RAM and lots of cores to play with for relatively cheap. If pics on Amazon are accurate, it looks like they pack them well. And honestly, for a system like these, which are surprisingly heavy for 1U and without original style packaging, that's a selling point even if it costs a bit more. 600GB drives...personally, I wouldn't bother with 10K drives at this point, but kind of nice to have something to start with?
But, that having been said, not sure this is the greatest price for what you're getting? Also as noted above, these are getting old enough that some of the newer OS & program innovations (that I'd want to tinker with as a homelabber) aren't going to be compatible. If I were needing a starter system, I'd think this would be a nicer choice (my opinion only and not associated with either of the OPs).
https://forums.servethehome.com/index.php?threads/lenovo-thinkstation-nice-server-workstation.40377/. Fairly similar price and a couple generations newer. And while the Xeon W-2135 has less cores to play with, its going to have more computing power. Plus, for a new homelabber, the tower case may be an easier fit?
Just my opinion. Cheers.