i prefer microbore 6mm. Though im using 100m minibore.
the 100psi pump is commonly used without problems. I guess 6mm will put more strain on the pump, but thats why some use a varistream. 8mm hose is going to hold a larger mass of water in the hose all the time, but no difference in saving water?
Minibore can make those annoying squiggles, almost like a kink, but it wont shut the water off. But once youve got it straightened out its really not bad, i havent noticed much with the flow rate, good stuff, i have found its a bit stretchier, like when you get it caught on something, or pulling it around a house its a bit stretchier. Though never had any trouble with flow on the 6mm stuff, found it didnt kink as much, and was a bit easier to handle. Whatever you get unroll the whole lot in a straight line on an industrial estate or something, then twist it so its not twisted up, then roll in on the reel, ey presto.