Thank you all for your replies. I have some info to share which I hope helps others. I have spent a lot of time thinking about what is the best thing to buy, to air up and down on the Metris.
I was very worried about the time it would take to air up and down the tires. I think it is more of a problem for people with HUGE tires on Jeeps, not the kind of tires we can run on a Metris.
I brought this tire inflator
from Costco because of the life time warranty they offer. It seems to work well.
I aired down to 30PSI very quickly using the deflator button on the compressor. It was fast like maybe 30 second per tire in 10 sec increments, you have to stop the air release momentarily to see the actual pressure. So I don't think I need any special equipment to air down. I was going to buy the ARB deflator.
To inflate was much faster than expected. 1 minute 30 seconds per tire from 30 PSI to 45 PSI. I run 225//65/17 BFG KO2 and 8" not 7" wide wheels.
I used a Lion Energy power bank to power the inflator. I power the Lion Energy from a 100W Costco solar panel mounted on my roof. I use a flat 12v cord which runs through the back door seals, to connect to the power bank to the solar panel.
I tripped the Lion Energy internal breaker at the first compressor start attempt. It ran fine on subsequent attempts. It probably exceeded the peak ~ 500W output momentarily. The alternative is to run the compressor from the 12v outlet if it supports 20 watts or directly from the car battery (with an adapter for the 12zv plug to battery clamps).
P = VI
215 = 12I
215/12= 18 Watts average power consumption
It turns out I had nothing to be concerned about. I also think I can run at lower pressures than I first thought as the Metris is around 4.5K lbs which is the same as a Tacoma, we are not Sprinters running at 70 PSI. It would be great if someone can confirm how low they have gone and highest speeds driven?
Tire at 45PSI - Note close to 2 pads in full contact
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Tire at 30 PSI - Note close to 3 pads in full contact
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Compressor running shows 215 Watts @ 12V
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