Dan, I think someone else also mentioned the same inverter you are using, I checked it out, looks like it is about $200, A little more than some that I've looked at... the standby current drain as you mentioned is important unless you want to keep hooking it up and unhook when it's not in use. I've seen the Wagan 400 for about $100 but in all the tests of that unit shows it's putting out just a little under 60HZ which is strange, all they have to do is use a clock to sync it. I have recently seen a review on the Powerbright 300 which sells for about $135. Here is a pretty good review
Bansai, good points, but the PureSine inverters are coming down to where one doesn't have to worry.. and, as you said, more and more are coming out.