My names boblo and I’m a mat freak…
Standard Thermarest… I have many. Warm, relatively bulky and not a total disaster if punctured. I then got a Neoair, great. Bit crackly, warm, compact and light. Developed a goiter after ~200 nights and was replaced with a Neoair Xlite. Warm, quiet, compact and a bit lighter. I prefer the classic Neoair though as it covers more of the tent floor, betterer for winter.
I’ve just bought a Numo for Mrs Boblo’s summer bike camping it’s light and compact though I suspect not as warm as the Neoair’s though she’s not used it yet. It was only £35 so a lot cheaper than the Thermarest though I’ve found this to mean less reliable in the past with a Fat Airic that developed a fault.
If for UK summer, try the Numo. It looks like a good warm weather option.