The gun on the trucks is MUCH bigger... it says the caliber in its description. THIS is the one that comes with the commander. There is no flak 88...
Well it could still be quite handy in building round ur trucks keeping light vehicles away and shredding blobs,sovs particularly would have trouble against it as they lack bazookas to qiuickly take it out...however if it costs fuel like the PE flakverling it will be completely useless.
Other thing to consider is if it will die to 1 satchel like bunker.
I still have hope for the 88 mm,lets wait for the other commanders.There will be one german commander with SP hummel/wespe at least.
Overall luftwaffe seems to be a good infantry centric defensive commander.Multipurpose eplacemnts,good infantry,machine guns,trenches and that airborne assault could be very useful in reinforcing ur strength when ur truck is under attack while also providing off map firepower.