I'm going to put my opinion out about these rings now.
The 4 sided ring works good to me because it's traditional, it's what all American wrestling companies use. I don't really see anything good, nor do I see anything bad about it, it's just okay. The 6 sided ring adds uniqueness to the company. No other American wrestling company uses it, so it looks cool and special. Only thing I see a problem with it is that the new guys need to get use to this more. More training to get used to the format of the ring. If I was running a wrestling company like Impact Wrestling, I would choose a 4 sided ring. If I'm a fan, it wouldn't matter to me, I'd just choose the 6 sided ring because it is unique and it's different, plus it's interesting to see how people wrestle in it and use it to their advantage.