To be fair, i have both . But my #1 favorite plastic is easily the XX.
If you dont care about fingerspins, shoutout to the Northstar. I got one during aMAYzing and it surprised me. But id still go Speedaholic XX given the choice.
I just picked up a YoyoFriends AoE from the rainforest for $10. I haven’t received it yet but it has a similar shape to the TopYo Mojo which has been my recommendation for a very good very cheap plastic for years. I’m excited to see if it dethrones the king
Hybrid fulvia is in the too 3 longest-spinning yoyos I’ve used (and, as you can see in my profile, in my top 2 favorites all around). If you’re looking for balance, I don’t think it gets better than the DD Monarch, which is also very long spinning.
As for straight up plastics, my experience is limited. I absolutely love my Shooting Star - would actually recommend over many monos. It also has a highly praised finger-spin dimple, and it’s cheap. It plays on the faster side, but has a decent amount of spin time (especially given its weight). There are likely more stable plastics out there, but it’s not really a problem for me, and it’s definitely better than the older plastics and several organics that I’ve tried.