- Quality wise I'd always go with neoprene / mousepad material. While more expensive they're just plain better than the other options
- manufacturers - my mats are all made by Deep Cut Studio, mostly because they have a large range of mats and also provide mats for Dropfleet Commander - but others at my gaming club went with e.g. gamemat.eu and we're just as happy with their mats.
Design wise I'd suggest taking a scroll through their inventory, and finding something that'll work with the way you painted and built your terrain.
Something like this
https://www.deepcutstudio.com/product/wargames-terrain-mat-urban-ruins/ should work with most urban ruin themed terrain, for example - but there's lots of designs like that.