Yes, it has the twist-loc. It even comes with a very nice, fat cord ... 30A, 4-prong twist-loc on one end, and FOUR 120v 15A plugs on the other. It is protected by the generator's main breaker.
For that matter, a 'power inlet' (with weatherproof cover) costs less than $20. As long as I only use "one circuit" worth of power I'll be OK. Plenty enough for a furnace blower and a few lights. Can't accidentally overload things if I have to swap plugs
Acorn? My rods are ... as code requires ... completely buried. I'll run the ground wire either to my 'inter-system grounding bridge,' or maybe even straight to the panel bussbar.
I specifically do NOT want to have a permanent connection. Choose loads? It's a bit too easy to mess up - and, before you know it, you might as well put in a proper transfer switch, etc. No, this is a PORTABLE generator, and will be used as such.
Keep in mind that this genny won't just sit there ... it also serves as my jobsite genny when I need one.