the ardisams are cheap but very powerful!
used them all summer long, easily over 1000 plants per auger and the only repair so far was getting a new pull starter put on the one powerhead.
it is extremely hard to get auger bits off the powerhead so we just switch powerheads- 8" for 1-2 gals and 12" for 3"+ gals. also ditch the bolt for a tractor hitch pin/lock ring setup.
you can get them $200 at tractor supply!
2 for the price of 1 echo!