The Kevlar hoses I have used in the past were terrible; quite a short service life. The original hoses lasted a good 10 years, so I thought better stick with Mazda OE. Not much more than the Kevlar hoses anyhow. The silicone hoses come with nonsense claims, such as lasting 10 times longer than standard hoses, ie. 100 years+.
Mazda hoses are reinforced rubber (cotton reinforced I think). The previous owner of my 93 car went mad with silicone hoses everywhere; 5 years on, it all looks a bit tatty. Some of it looks very ill fitting.
I recently bought a set of silicon hoses from a Chinese company on ebay. Just under £90 for a full set of 8 hoses for a MK2. I believe they have MK1 hoses as well. They haven’t been fitted yet, but they look very impressive. Found some good comments on the net from people who have them and a lot of nonsense from people who haven’t.
ive fitted the silicon one they seem ok but one of them seems to squash as it goes round the bend dont know how much it affects cooling but it concerns me a little