OK, I will possibly get a Testo 560 or listening to others here, the Digicool might be interesting. Digicool website is bollocks as it doesn't tell you anything about valves or how to attach anything and there seems to be no manual you can download to see whats what.

Anyone had any real experience with it or got a digital manual?

Also, as Honeywell has a new R407F, how would an existing digital unit work with a refrigerant that doesn't have it data on board.

digital is all new to me so don't want to make a mistake