Just bought a 770 and should be here tomorrow afternoon. I'll let you know what I think of it. Of course if you do too much reading on here it would seem the 770 is an inferior weakling.
Our 770H was in the field for 3 years and the first fail was primer bulb. I woud not buy any 4mix unit if you want longevity. The covers on these units are solid. For those who had PB650 UNITS this model just might match up. And if you need more blowing force you are doing some wrong (I.e. pushing leaves long distances).