Long post-
I too had a difficult time deciding between Redsea, waterbox, innovative marine, glass cages
Redsea - From what I could find out and chatting to people on a Facebook group called “Redsea uncensored” there are still spot failures on the G2. No incidences so far with the G2+ but it’s just been introduced ie ~ 1 year or less.
Red sea with the aluminum stands never had any failures. So any of the Reefer-S 550, 750, 850, 1000 G2+ with aluminum stands never had any reported failures.
Redsea has armored ie protected silicone seams.
Waterboxes - saw it in the LFS, good quality, aluminum stand is less robust than the red sea or Innovative Marine aluminum stands. Also hard to reach their customer support.
Innovative Marine - robust stand, silicon seams are nice and thick. Options for external overflow. The sumps are huge ie for anything smaller than the INT 200 or EXT200, sump occupies entire stand(good because now there’s a nice refugium area, bad because all control equipment has to be outside of tank or need some creative arrangement). Great customer service, always able to reach tech support via phone or emails. Larger tanks like 170 above have Eurobracing, also glass is thick.
Glasscages - Great reputation, can customize anything, has metal stands as option. Longer wait time. Plus the owner Joe is very helpful. Lifetime warranty.
Reefsavy- robust tank, pricey for one of the top tier tank makers. They are very busy but still does reply.
FYI - I wanted an external overflow that’s easy to clean out and see if any aptasia is hiding in overflow. So I went with the IM 100 EXT. I managed to get a roller filter installed in the sump. The overflow is a bean animal, easy to adjust and totally silent.
Red Sea offerings are all Herbie style overflows, needs more adjustment from time to time and a noisier if pushing a high flow rate.
redsea, IM, waterbox comes with pre assembled plumbing. Only IM plumbing is compatible with schedule 80 or 40, while the others are metric.