Had Next SLs on my Alpine since May 2015. No major issues except I broke the cheesy bearing tensioner and it cost £15 to get a new one and was difficult to source. I changed to an Oval ring early this year and cleaned everything up then. I noticed a bit of grouch in the BB one side but it’s been spinning fine since with zero play and I’m hoping to get this winter out of it before I’ll just change it. Making it two winters and one summer from a BB (1,275km ridden so far on it).
No issues with pedal inserts yet. I make sure the pedal threads are greased regularly. Superstar Plastic flat pedals. That’s bling on bling, eh 🙂 They’re great pedals.
They’re super nice cranks and they made my bike 1lb lighter. I too feel the BB (BSA) is the let down but it’s outlasted my expectations by miles and I even bought a spare BB to replace it many months ago.
Lifetime warranty with Next SL I believe. Hopefully that really means lifetime as I’m hoping they’ll go from this bike to my next one when I change and still be sweet.