Not being a user of either, I was interested in user comparisons between these two brands of housings.
I have used both, albeit briefly.
Both kept the water out! 
Equinox have excellent sales and service. Very helpful. Personal approach. Proactive follow-up.
Ikelite had reasonable sales and support, but a little "mass-market", if you know what I mean.
I stopped using both because I never became comfortable with the manual rod control system. Too fiddly. Too slow to operate when something important comes along.
Neither had a really great monitoring option. The Ikelite has a mirror arrangement on the side. Not intuitive, especially for macro subjects. The Equinox has a monitor in line with the lens but, because it is mounted vertically behind a very thick perspex panel, your head needs to in an unnaturally low position, placing the whole housing tube between the eyes and the subject.
Ikelite flat port is a bit limiting with the usual corner sharpness issues. Equinox has a semi-dome that gives good images.
The Equinox had an additional problem in that it weighed a ton. Because of the cylinder design, there is a lot of air inside to compensate. Their ballast design uses special shaped weights, one inside, two built into the handles. So you have to take them with you. Very heavy. Nice for UW stability but a pain on the boat and impossible as a airplane carry-on.
Regards
Peter