I've had a few 190mm brakes over the years Geoff, and found them to be variable in operation, (some good some not so good) trying all the usual fixes including linings. The best result being a TLS brake plate.
When I made the double brake, I did consider using A65 8" hubs as they have a wider drum and shoes, but there is insufficient width between the fork legs.
I used standard 8" Goldie hubs, modified as required, it's a superb brake, the down side being, the increase in unsprung weight.