Most of the Head units have a seperate inline fuse of only 2-5 amps. I would bet as long as you are not working it hard your vending machine unit will do the trick nicely. I built my own 12V PS and I have used it many times to help diagnose some electronic issues on cars as well as drive car stereos in my house. it only has 5Amp out put.

Jason
M80 v2
VP160 v3
QS8 v2
PB13 Ultra
Denon 3808
Samsung 85" Q70