Your thoughts; Most accurate and quiet pcp on the market?

You could buy any of the decent-priced to the high-end, mega-dollar PCPs out there and ALL will have the SAME accuracy provided you know it WELL enough and HAVE the skills to extract that accuracy out of it. And that is why I am unable to state specifically which guns are the most accurate but will at least say that ANY OF THE RIFLES mentioned by the above posters WILL SHOOT TO YOUR ABILITIES.
 
Tapian Mutants are very quiet guns in .22/ generally guns producing around 30 fpe or lower are able to be tamed to much lower decibel levels. Shooting out to 50 yards gives you many options that may work well.

2nd that

I currently have 4 guns in my collection - in terms of loudness

1. Steyr Hunting 5 - without a moderator this thing will bark!!

2. Edgun Leshiy - the built in moderator is very good

3. Huben K1 - the built in moderator is surprisingly good but the action is loud to the extent I need to wear an earplug in my right ear!!

4. Taipan Mutant Standard - very quiet muzzle report and action noise