Have you thrown away your wheel covers yet? That is a far greater impediment to checking tire pressures! Once you get rid of those things you can easily check the six tires in 5 minutes. Fancy stems would shave that down another minute or two. You do need a pressure gauge with a straight on end, no 45 degree angle, for the inner wheel and an angle only on the backward facing end for the outer wheel.
I bought my tires at Costco last year and they had only two choices for stems - short and very short plastic ones. I took the short ones. Costco did a nice thing, installing the dual wheels so bothchalcedon stems are in the same rim hole - another minute saved. I do have one inch plastic extenders on the dual wheels, mostly so I don't need valve caps. I have not had any trouble with them so far but after my experience with another kind, I carry a short piece of hose I can use to whip one of those extenders off in seconds if it fails to close after a pressure check. And a 12 V air pump.
The little hose idea is very nice on the car in winter, too. Take a valve cap to a hardware store and buy six inches of hose that fits snugly on the cap so you can turn it off without sticking fingers into the opening in those stupid wheel covers.
With this tool, I could keep valve caps on the MH duals. It would only cost two or three minutes more in pressure checks.