Thats a good price... The Honda units would be my first choice but these are becoming pretty popular now with the RV'ers..
Will be pretty heavy to roll around and lift up into back of truck where using two 2000Watt Honda EU2000i models would each weigh less... You can get appx 3600watts (usable) from two 2kw Honda generators hooked up in parallel. I suspect you will only get 2800 WATTS (usable) from the Champion 3100 model...
I think I read these 3100 models weigh around 95lbs
Might want to consider if the 2800 available watts will run your air conditioner OK