[Closed] Do I need Knee pads?

So I've never had them before and haven't had the kind of wipeout where I think I would - but a lot of riders seem to have them on the trails I'm on?

Basically I ride the red routes/black sections at Trail centres and have been taking on more and more 'All Mountain' routes - Helvellyn, Snowdon, Bothy finding in Scotland etc.

What are peoples opinions?

Been looking at the Nukeproof Enduro knee pads - http://www.chainreactioncycles.com/nukeproof-critical-enduro-knee-sleeve/rp-prod132015 - any good or would you recommend something else?