Mathieu,
Ikelitre is a very experienced uw-housing manufacture, is building housings from far 1962 and a lot of excellent photos were made with Ikelite housings.
I have 2 Ikelite housings, one (my first) for a Fuji E900 and one for my Nikon D90 and I never had any problem with it.
I see no reason why Ikelite housings should flood earlier/easier than a aluminium housing, but if you consider to drop, bang or hit it, a aluminium housing will be sturdier.
On the contrary, if it should flood you will see it much earlier than a aluminium housing as they are nottransparent and due the transaprent housing you will also see the o-rings and if they are "squeezed" well.
But as Bill wrote, think first about the camera AND the strobe(s) you would like to use and then choose the corresponding housing.
Chris
P.S. One hint regarding your camera choice: Don't buy a exotic camera, you won't find a cheap, used replacement if you flood or break the camera, but to get a replacement for a widely selled camera like a Nikon D80/90/3000/5000 oder a similar Canon model would be not a big problem.