I have put it on mine. Had same questions as you have.
Before tenere i rode KTM 990 ADVENTURE S, with WP suspension, so you can imagine how sucky the original regular ten susp felt like.
I ride my tenere quite hard, so i bought Hyperpro.
Got it at Calsport, cheapest: http://www.calsport.co.uk/

After change I wasn sure, but after some tuning i find it quite good. I went on enduromania rally, ant felt if I wouldnt had Hyperpro, I would probably brake mi bike.
With this mod, bike will eat holes better, handling will improve, shorter braking distance. You are able to sinchronise the softnes, and still ride hard, without putting the suspension to the end. (dont now the exact word for it)
Also bike has les dive when braking.
Understand this is no complete some kind of WP upgrade, but just progresive springs does some of the trick.
Hope this opinion helps.
If you find my posts here, you can see how i ride it, so it might work for you also.