How are you going to mount those panels? I think everyone on here is going to say flexibles are junk, maybe not as big of an issue if you're only putting them in the sun occasionally. But then you'll have to build some sort of skeleton for each panel that can fold up, not blow away, and resist bending. That's just adding weight and bulk, negating their purpose.
Just seems like a pain in the ass to carefully set out flexible panels, angle them, anchor them, connect them. So much of a pain in the ass that I'd skip getting that kit all together. Strapping three flexibles to your truck (roof, hood?) and wiring also sounds like a messy pain in the ass. You'd also have to park in the sun if you attach them to the truck, which may or may not suck depending on how late you sleep.
Maybe consider 100ah Battleborn ($950), 2 x 150w HQST rigid mono panels with some aluminum from lowes/home depot to make folding props ($280 total), and a Victron 100/30 SmartSolar charge controller ($200).
That puts you at $1430 and a setup you can distance from your camp a ways. With that saved $170 you could get a Victron BatteryProtect and cover half the cost of a BMV for measuring capacity, things you'd be wise to purchase in addition to that kit anyway. You could even skip the BMV and use a TK15 coulomb meter, bringing your total cost below the kit you linked.
If you really want to cover the truck in temporary solar, give consideration to the folding 100-120-whatever watt panels that can be found in abundance on Amazon right now. Not as much bang for your buck as rigids or flexibles, but will be more gentle on your paint and less of a pain in the pecker to secure.
theinverterstore.com
