In reply to steveb2006:
Adidas actually bought 5.10 back in 2011 but it wasn’t till recently (maybe beginning last year?) that people noticed some difficultly in finding pairs for sale.
Looks like this was associated with a change in production process around the same time.
I think some people said they’ve noticed a difference in the shoes now and others haven’t. Give them a try and see for yourself I’d say, though bear in mind a new pair is going to feel vastly different to an old worn in pair even if they were produced identically!