Fly rug for thin skinned, easily rubbed horse?

[Barlow]

I don’t normally use fly rugs but on vet advice ahead of some forthcoming treatment they’ve recommended using a fly rug.
So far we have tried a lightweight mesh rug in a couple of different brands but they have rubbed him in weird places (along his flank) as well as around his shoulders, despite the claim of Lycra/satin lining on the shoulders.
Any ideas on what I could try next? Either something that is very very soft mesh or something that simply isn’t a mesh! I was looking at the Aussie all rounder style and wondering whether they might be softer?

 

[Flowerofthefen]

I really rate the aussie allrounder.

 

[Lucky788]

Amigo bug rugs, I really like them nice and soft but don’t slip back

 

[rextherobber]

I use the Shires bib under a Mio