"Charging from the generator is my biggest concern"
If indeed this is your BIGGEST concern a multistage converter with remote pendant will decrease the generator run time.
How much? Well that depends...
For any of us to make a proper suggestion we need lots more info regarding your power requirements, battery bank size and type, etc....
As stated by the others - The 7345 is a good quality single stage converter. There are many quality multistage converters available or you could simply take along a 120Vac portable battery charger - hook it up to the generator and have both the 7345 and the charger top off the battery.
Many many options available
