This is my First post, thanks everybody for all The great info all of u guys Put out. But heres my question, i have a 2 month old 2013 Marin Rift Zone & it came with Avid5's, my rear brake kept loosing pressure. Avid/Sram warrantied my whole braking system (fr & Rr) with Sram Guide R's... While it is their best new stuff, The Guide R's are The lowest in The line. My question is do u guys think They will be Better than The avids??? Lots of reviews on top line Guides, but none on The R's. Any one have experience with Guide R's???