As far as I can tell, there are three important torque values on the Grenadier: wheel bolts 160 Nm, front wheel hub 360 Nm, and rear wheel hub 600 Nm. It makes a difference whether I want to tighten or loosen these bolts. Loosening usually requires a higher torque.
For most jobs at home, I use a small Facom NS.1600FPB pneumatic impact wrench, which can tighten up to 860 Nm, but loosens bolts with over 1000 Nm. This little thing is a beast. I've only ever used it on setting 1.
If I were to buy an electric impact wrench, I would go for the Makita 700 Series for weight reasons and its smaller size, as I already have other Makita cordless tools.
I could easily loosen the rear hub nut with the Makita 1000 Series impact wrench, but it's much too big and heavy for any other work and the question is, if I ever need to loosen this nut.
Unless I am also consider bringing a cordless angle grinder, a cordless blower for the grill, and a cordless chainsaw and of course some chargers, I would avoid using a cordless impact wrench while on the trail, as I'd have to ask myself where the end point would be. The few times I need to loosen screws on the trail I can do it by hand.