@ DG thanks for your comments
webmaster, sound like you are just defending the customer service that does not really know what they say. when I call and I press option 3, there MUST be a reason for me to do so. Option 3 is infact is the department for pro-jump.
Now you are saying that maybe people that answer at the call are not from the sector. Let be honest, they are just at the phone like robot answering the call and they even know what a pro-jump is!
Its 1 for UKGooddeals, 2 for GhostBikes and 3 for Pro-Jump, however the calls are answered by the same group of people, what happens is, when a customer calls in and chooses an option, it is displayed on the screen so that it can be answered accordingly: ie Thank you for calling Pro-Jump, Alex Speaking, How can I help?
The staff are fully aware of the product and its specification. However the staff are advised to say, that although most springs are interchangable, we only recommend the use of Pro-Jump springs in a Pro-Jump frame simply due to the slight variations of the versions and if you damage the spring trying to fit it to an incompatible frame you will invalidate any warranty, as even with the newer Pro-Jump Spings, if you have an older frame slight modification in needed.
In response to your original question:
Does pro-jump SPRING fit on POWERIZER?
Yes they will fit, however depending on the version you may find that the newer spring is a lot harder to get in and that you need to "shave" some of the rubber buffer that is on the inner side of the metal hoof.
About they got a mixure of carbon and fibre, it is a bit weirdo ? from what u are saying, i can be lucky and get a carbon, or un lucky and get a fibre glass. ( the difference of price of them is different if you look the site i posted early ) it is like you are ordering a chain in silver and u got one in white gold! 
If you are ordering from Pro-Jump we have never differenciated with the springs on price, we have not increased the price on the carbon mix springs or lowered the price of the fibreglass ones. The company that you linked to, talks about a 30% strength increase in the carbon mix springs however there is no factual evidence of this nor is there a real way to test this. With regards to performance, many people find that the carbon springs are a lot more responsive than the older ones, however we still have some customers who prefer the older ones as they find the carbon ones a lot stiffer. If you are ordering from Pro-Jump you could leave a note requesting that you would prefer the carbon mix ones, if they are in stock then you will get these.
