As a Biocube owner, I would say the Biocube is pretty amazing. It definitely has its pluses and minuses like previously said. I would say there are more pluses than minuses though.
Pluses:
Pretty much all set up for you except for some basic things (ie heating, biological and chemical filtration. comes with one monthly replaceable mechanical filter)
Able to be modified easily
Awesome design
8x turnover rate
Minuses:
Quite a few modifications are going to be needed. inTank has a lot of good options for modifications.
Stand is ugly IMO and there’s not really any options for other stands besides DIY
Lights may not be strong enough for SPS, but softies and LPS should be fine.
I bought my Biocube from marineandreef.com in a bundle that I’ll link below. Highly recommend buying one of these two bundles if you get a Biocube. It’ll save you hundreds I promise.
Bundle with stand:
Coralife Size 32 LED BioCube Aquarium Deluxe Reef Package
www.marineandreef.com
Bundle without stand (I bought this one):
The Coralife Size 32 LED BioCube Aquarium Deluxe Reef Package combines everything you will need to get your BioCube started. NO Stand.
www.marineandreef.com
Stability will be better in the Biocube because there will be less fluctuations in parameters. Bigger is better for reef tanks.
I hope my input helps. I’ll be happy to assist you with concerns.