I played on this server before it was known as Apollo (Hades), and ever since then, I have played every fresh release they've offered. The quests and zones are scripted perfectly (Loremaster is easily achievable for both factions), dungeons/raids may have rare or occasional hiccups but are completable, and PvP is always popping, especially within the first few months of the fresh releases. The newer relaunch will come with more Quality of Life changes, which I am looking forward to :D Can't wait for Nov '23!
If you're okay with joining a server that is fully progressed and doesn't even have enough players to do more than one (1) 25m per week, I will not judge. (openly) Project Neltharion sounded like it had promise at the beginning, but upon opening had more crashes and bugs than total players. If you don't want to waste your time, I highly suggest waiting until Nov 2023 for Apollo's Cata server.