I've got an X-600 on order with a Merc Opti 135 on the back, due end of May.
On the contrary, aside from the console and A-frame these boats have nothing to do with Tornado. They are built by a UK manufacturer who are expanding into the budget market. However they are remaining hidden at the moment until 2005 when their will be a full european launch of the ribs. The reason for this is that they already make larger more expensive ribs and a launch now may stir up some tension.
This manufacturer, no doubt has definitely taken a cue from Tornado with the A-frame and main console but that is where the similarities end.
As regards the ride with the flatter hull, I think you will find that the hull of the X-Rib is actually deeper towards the rear. I've compared measurements with my friends, Voyager 585. The hull on the X-600 and X-650 is very similar to that of the larger Tornados, the 645 and 695 with a newer triple spray rail design. The tornado 585s still have the old 2 rail design.
Funny thing about the polyurethane tubes, people either love them or hate them. Be sure that you're not mixed up with PVC tubes which are the type that crack in the sun, etc. See this link
http://www.wing.com/polyurethane.html
Read the bit in the Naval report at the end.
I know this has also been discussed before and PU tubes have been mistaken for PVC tubes which are in fact more closer to Hypalon than PU.
My boat should look like this, but with grey glass and a Opti 135.
Great boat for the price!! Package deal even better!