I just overhauled my entire synology array and my original purchase was two reds and two seagate ironwolves. I ended up returning the reds because they were disconcertingly loud and performed poorly, which it turns out was probably because they were SMR drives!

I'm using four of the seagate ironwolf drives now and they have been fine so far. Equivalent price point and capacity, slightly quieter than the WD. Just make sure to check whether you're getting SMR or not - the ironwolf NAS drive line is not SMR according to Seagate's docs that I read but definitely verify for yoruself.

You can buy a Red pro, have a look at that list:

https://nascompares.com/answer/list-of-wd-cmr-and-smr-hard-d...

If you want to stick with WD, you can still buy WD40EFRX, which are not SMR, at many retailers. Of WD's current product line, you want to avoid the EFAX, EZAZ, SPZX, and SPSX models.