from my own experience, J-Mat channel water when compressed stacks (one on top of the other) in barrel prefilter. in term of durability, J-Mat stood up to abuses really well e.g. high pressure water spray, bang on the cement, shake in the pond,...,etc. it hold up very well after two years of beating.
I have not use Matala but its webpage matalausa.com gave a good explanation of how the product performs or intended design to perform. I wonder if there is webpage that have similar info on J-Mat. I did a search but didn't find any url with such of info.
I agreed that matala cost a little more but if it performs as described, then it's worth to spend the extra money.
Steve