jd950,
To spend 2x the amount of the camera on a housing was counter intuitive for me. I could just by another S90 and OEM housing for the price difference involved if I should encounter a flood with the OEM housing.
You seem to have had a lot of camera/housings. Is this a result of new models coming out that supercede the technology of previous models? If so, what parts of your system have remained compatible and usable through the course of the upgrades? You also seem familiar with the INON System which I have been looking at closely as a basis for my re-entry into the hobby.
It is common for aftermarket housings to cost approximately 2x the camera price. A lot of the price is simply due to the fact that for all the research, design and manufacturing, there is a fairly small number of any housing sold. I would guess most of these sell in the single digit thousands, maybe even in the hundreds.
The pricing for DSLR housings isn't so controversial because there is little choice. For many of those cameras Ike is the economy choice, or you pay what it costs for the premium housings. For compact cameras, there is more competition, at least when the camera Mfg. offers a housing. That makes the premium housings seem outrageously expensive, but for a few years now, there has been little opportunity to use add on lenses on the premium canon compacts and that created a void that Fix and 10bar and Ike filled. I think for some potential S90 buyers, the value of the fix and Ike housing suffered a bit when Inon came out with the AD mount for the OEM housing.
The Fix housing is not unreasonably priced for an aluminum Japanese housing. I am not an Ike user, largely because of my Inon strobes, so I just don't pay attention to their products. Because the OEM housing with the Inon base now offers similar lens options to the Fix, the decision between those two housings is harder than it was a couple months ago, at least for me. I guess it is similar to comparing a Lexus to a Hyundai. They both do the job but for some, the perceived quality/desirability/performance/features or comfort makes the Lexus worth the price, while for others, not so much.
I think if you get the Fix housing it would probably be with the idea that you would use that housing and camera for some time. But, the housing will have resale value, so it isn't like you throw it away if you want to upgrade, especially if the S90 successor can use the same housing.
The changes in cameras from year to year often don't make much difference to underwater use. On the other hand, the S90 might change in significant ways. There have been complaints about its free-spinning rear control wheel and the lack of HD video. Perhaps one or both of these things might change. On the other hand, they could also increase the zoom range and render the camera much less desirable for underwater use
I have had so many housings because I had an earlier Canon and OEM housing and after a couple years wanted to upgrade to a larger LCD and some other features. My son then grew fond of that camera and housing and stole it from me, so I got another, similar model. I later upgraded to the ability to shoot in RAW. I then upgraded to get a camera with a wider lens. My strobes, focus light, tray, handles, arms and so on have carried on from camera to camera, but that is all, because I have no add-on lenses. My knowledge of Inon lenses comes only from reading and talking to others. I have no first hand experience with them
If you are just starting out, I would suggest giving a lot of thought to the OEM housing for the reasons you mentioned. Strobes and a wide lens will have more impact on your photography options than will the housing (so long as you can shoot the lenses and strobes you want to).
(I overlooked your prior comments about using a housed Nikon. Since you are familiar with using an SLR underwater, I wonder if you would not be happier getting a DSLR and housing it? Perhaps even a used one? Another option might be one of the new micro 4/3 cameras)
I would forgo the fancier housing before I would forgo a strobe, but if money is not an "issue" and you can afford the Fix housing and the strobe(s) and the lenses you want, then why not get the nicer housing. I don't think there is a downside other than money. If you are careful with O rings, I think it is likely that you will "need" to upgrade to the latest and greatest before you will need to replace a camera due to a flooded housing, no matter which housing you get.
I know I frequently suffer from that "need to upgrade" foolishness.