Dave,
Our truck's inverter is rated at 440 watts, so I think it would be okay. However, your point about getting something cheap and unreliable was my original concern. I see that Viair makes a less expensive model that may be a decent alternative for only $67 on Amazon. I originally thought it would be nice to have AC/DC plugs for versatility, but at home I have a larger compressor I can plug in and use.
https://www.amazon.com/Viair-00088-8...-search&sr=8-3
Regarding the tires, they are ST225/75R15 listed as "load range E." The tires were new last year and I think the sellers said they also kept them at 65psi. I feel like I've seen that number in several threads, though I know some people tweak the pressure in different conditions. I just wasn't sure if there was a more specific recommendation for the tire pressure determined by particular model/weight.
Thanks.