I have a couple of these, »
www.amazon.com/Watts-Met ··· 01B6N2WK and they are quite handy. I know they cost more, but they are great at quickly checking things. The lower left number scrolls several different measurements, Vmin, Wh, Ah, Apeak, Wpeak.
I added power poles to them so I can just snap them in and out of circuits real quick.
On that page I also see what looks like a G.T. version of it for quite a bit less. I guess a couple USB to Power pole adapters might be needed for your application.