Is there any particular reason why the manufacturers of these things just stopped making them? I'm assuming it is mainly due to lack of sales??
Yep....
1) They were CRAZY expensive for a boat, that didn't even come with an engine. The one in your link was $30k !!!!!!!!!! I can buy a nice NEW boat, and a NEW ski for the same $$$.
2) You were trying to sell a boat to the jetski crowd. Most guys who have skis, don't really want a boat. AND... most boat guys HATE the skis. (we are referred to as water lice by some)
3) That big one was SLOW. It was a cool idea, but even with a 130 hp ski plugged into it... the drag was high enough, that they would only get to the low 30's.
4) Because of the design (especially the small one) it was big, but had a lot of wasted space.
5) In some states... it was hard to register. They didn't know if it was a "Barge" (no registration) a non-powered boat, or if it was an extension. Since the ski wasn't bolted into the SC... the total capacity didn't change. SO... you could get a ticket for having more people for the capacity of the original vehicle. (like putting 4 people on a tube, behind an x4)
OK... with that said... I always thought they were kind of cool too. I could take the ski off, and let the kids and wife swim. But... here's the caveat... Over the past 20 years... I thought they were cool. BUT... never once did I go to look at one with cash in hand. (see what I'm saying?)
Because of low sales... 3 companies tried to make a go of them. (all under the same label) Also... the re-sale sucked. As SDB said... it's not a universal fit. SO... if you have the rails for an x4 hull... You can't just stuff a GTX (or whatever) into it. Back in the day... the rail kit was $$$... so to change the skis was expensive. And finally... if you rode it aggressive... the rails would brake, and scratch the crap out of your ski.
For them to have been successful... they would have needed to be under $8k on the trailer. But even the little on was closer to $18k by the time you bought the special trailer, got a top, the rails... and paid the tax, and reg on them.
A few years ago... there was a new company trying to make a universal fit hull. I don't know if it worked out... but I haven't heard anything about them.
So... to sum up:
1) crazy price
2) wrong target market
That's my story, and I'm sticking to it.