Thanks for all info guys, the Sirmar funnel does indeed look fine but I've waited nearly 5 months I think that's it for me, I wasn't entirely happy with my funnel as it was, I'd used .5 styrene to sheath it and the skin was I bit flexible so I thought I'd add another .5 skin now it is a lot stronger and also gave me the opportunity to cut out the vents before I bonded it on, it gives a recessed look to them that I prefer to mounting them on the surface.
I added the capping and I am now happy with it, and it still only weighs 55 grams,
I had seen the Fleetscale domes but didn't realise they were hollow, knowing I could always get them if my hollowing out of the ones I've got failed, I had a go at one it started out at 62 grams after hollowing out it is now just 22 grams which I think is acceptable if I don't screw the other one up I will use them.