Hello,

Went down to local safety shop.

Broadly : Silicon facemasks more comfortable and more expensive than rubber ones

Cheap option 3m 7500 ( lots of hits if you google it) good reports from people who wear glasses - exhaust air pointed downwards away from glasses - flat profile so can wear conventional visor

Expensive Option : They sell a lot of these
Sundström full face mask SR200

(They aslo come as a very much cheaper dust mask only.)

They are interesting as they convert to a powered facemask simply by purchasing the pump if you want to and plugging the hose into the filter socket, Very expensive.

There were other in between prices - well worth a visit down to your local safety shop.

Will keep looking.

Bill