In reply to ScraggyGoat:
Picked up a another puncture last weekend, followed by one last night. Thats three trips in a row, including one night on frozen ground at minus five with a slowly deflating mat. Given all bar one of all punctures to date, not just the recent three are on the upper side of the mat, and all are exactly at the edge of one of the dot welds, it would seam to suggest either the fabric doesn’t age well, or I am very unlucky or that Sea to Summits dot weld design has a serious flaw.
going to email them, not expecting much, but fingers crossed.
Post edited at 17:56