randomly mine seems fine after its bizarre issue. So, despite blasting off the frame and jamming up, a strip down and reassemble (after seing no obvious faults or damage) its now working perfect. Bafflement...
I think stock I'd advise 134 or maybe the Abbey midweight gas - someone remind me what its called?
I think I'll look at green again when the AS reinforced nozzle is released. Will probably stop the nozzle breakage, but might still be putting other strains elsewhere - time will tell I suppose.