Appreciate everybody's helpful inputs! I ended up purchasing the Power Bright APS600-12 600 watt pure sine wave (PSW) inverter a few weeks ago from Amazon. Decided against a larger inverter because I had no need to power larger appliances like a microwave and really didn't want to invest in or maintain a second battery. If I need to use the microwave, I'll just power-up my inverter generator for a few minutes. Anyhow, inverter size aside, thought I'd comment on my experience with this inverter so far.
First off, the APS600-12 seems to be one of the highest rated 300-600 PSW inverters on Amazon. The three areas of concern for most reviewers appear to be reliability, fan noise, and power handling. During the last week or so I've been subjecting this unit to loads at its rated output for extended periods of time. The heat sinks get pretty warm, but zero issues so far. The fan turns on and off consistent with load. Heard a lot of complaints on Amazon about some inverter fans turning on randomly under low or no load conditions. As for the level of fan noise, it's not loud for my tastes, but I'm sure there are some who might find it irritating. Lastly, where this inverter really shines is power handling. The APS600-12 is rated at 600 watts continous and 650 watts for 20 minutes. Amazingly, I'm able to power my small 650 watt coffee maker with this thing! Even more amazing, I'm also able to power a Shop-Vac Hang-Up Mini wet/dry vacuum cleaner which is rated at 6.2 amps (744 watts)!! Pretty darn amazing considering this is an inductive load with high start-up surge current. I even switched the vacuum off and on quickly to try and purposely overload the inverter, but it still hung in there like a champ!
Bottom line, I think this is one heck of a 600 watt PSW inverter for $165-$170.