Part I

I have trees. Lots of trees. Very tall. They tend to litter up the roof with a fairly heavy leaf load, and it all ends up in the rain gutters. So, along comes iRobot and provides me a gizmo that *claims* to be the ticket to clean gutters...
And of course (being the Gizmodo Dragon) I plunk down a wad of dough and say "ship it." iRobot Looj PS do NOT pay $130. find them on eBay brand new for $60 (including shipping)

Bottom line: Looj gets a C-. Passing but barely. Also keep in mind that my place is this thing's worst case scenario... My gutters are also 30' up mostly, so *VERY* hard to clean, even with a really tall ladder.

Pros:

• gutter is clean
• probably cleaner than if I would have scooped it out.

Cons:

• Pine cones are its nemesis. It won't really flip them out of the gutter and it gets stuck on them.
  
• It took twice as long as if I would have scooped it.
• Track came off mid-way, and i had to manually retrieve it.
  
• flipped over in the gutter several times. the torque of the rotating flapper is enough to flip it, fairly easily.
  
• antenna gets stuck on gutter, and in fact in the track. antenna needs to be a lot shorter, and prb integrated.
  
• Gets high centered on pine cones, and debris in general. Make sure you let it really clear the debris before moving forward.
  
• flapper gets stuck, makes a horrible whining sound... so i backed off a bit and then went forward an inch at a time.
  

I had to watch the thing and control it from the top of the ladder (read: sprayed with gutter crap). Control from the ground at a safe distance failed miserably as it flipped and stopped several times. Clear a 4' section and then cautiously advance only a small bit at at time.

I had to move the ladder 5 times. if this had been more than a 30' gutter only 10' up, it would have been a severe pain in the butt. I am a great fan of automation, and robotics, and this little device is sort of neither. I am probably going to keep it but modify the flappers so they are a bit smaller (less flip-over torque) and probably remove the (mostly useless) brushes. BTW don't drop it from over 5'. (it fell off the ladder) it will survive but mine bent the flapper spindle, and i had to correct it (bend it back) or else it would have been off-center.

For those of you who have the Roomba, I still think it l ROCKS btw. Looj not so much...

iRobot folks if you are reading this, here are some suggestions:
brushes suck. get rid of them or make them stiffer.
flappers have too much surface area and contribute too much torque.
stuff falls on top of the device, and it just carries that stuff for the length of its ride.
when going backward, it needs a "cow-catcher" kind of thing to move debris away from the center and the tracks.

Part II

After Modifications

So I decided to try it again, this time with some mods. I wound up the antenna a bit so it doesn't get stuck going under the nails holding up the gutter. You can see in the picture that it's wound up behind the unit. Doesn't hurt reception too much, but farther away it might. The antenna actually acts a bit like the "cow catcher" that I wish they'd had. I might still make one out of a piece of wood or something and bolt it to the back end.

I made two modifications to the front end. I chopped about 1/2" off each of the ends of the rubber flappers so that it would have a bit less friction and a bit less torque. Then, I used ty-wraps to bunch and tilt forward the brushes so they don't get caught in the tread.

I tried a second gutter, (admittedly not quite as densely populated) and had success with the device. It got the flappers stuck a lot less (only a couple times actually). It didn't flip over, and it didn't loose traction. I went back and forth an inch at a time or so, just to let it flip the stuff out. There weren't any pine cones, so I don't know if it's a fair comparison to the first gutter...

What ended up happening actually is that the rotation of the flappers (rotating toward the roof) was flipping the stuff back up on the roof, where it would roll back down and get flipped again. only a small part of the leaves and needles actually got flipped OUT of the gutter and onto the ground. Not sure what one would do about this, but it seems like sort of a design flaw... If I turned the auger the other way (rotating away from the roof), it wouldn't flip anything out, because the shingles reached down actually into the gutter, and they blocked the thing throwing the leaves out. I actually had to break off a couple of the shingles over the near part of the gutter, just to get the device into the gutter at all.

So, I would recommend these small modifications to your device, as they seemed to help a bit. Good luck with your gutters...