I use jet blue from plumb centre 'cause it's good for gas and also potable water.

Some people wrap a turn of ptfe around an olive.

I never trust a com,pression fitting. Only use them where manufacturer has provided them and there is no other way of connecting to their appliance. Never use them by choice.

They use them a lot on board ship and never use a compound, but they also get a lot of leaks which they don't give a toss about. Youve got decorating and carpets to think about.