It took me about half an hour to install. The installation is not impossible but you have to apply a lot of leverage.

First, the accuracy improved.   I only tested it at about 45 yards and got smaller groups than before. Some 2-shot groups were as small as 0.4". Would be interesting to see what it does at 100.

I am pleased with that. I could never shoot such groups, they were considerably larger with open sights -- mostly because I never did get a clean sight picture.

Now the downside:

1) The Mojo sight is not adjustable. Once you sight it in at some range, that's it. You cannot go from 100 to 200 meters as with the original open sight. I knew that, and I didn't care because all you have to do is know the trajectory at 200 - and it is not an issue anyway. I like the fact that it is fixed.

It comes with a tiny Allen screw (not sure what it is, 1/32" maybe) to adjust the sight. You can however, count the number of
revolutions of the adjusting screw. 1 full turn means 4 inches at 100 yards for drop and 3.5" for windage. But it is not quick and you need the tool, which is tiny, and can get lost very easily.

2) While it self-evidently results in better accuracy, it is still not as good as a real peep sight. That is not a problem, 2MOA from AK is outstanding. I haven't yet tested it at 100 or 200 but thus far it makes me optimistic.

3) The biggest drawback -- while you gain accuracy (in my experience anyway), it is slower. The sight picture is slower to acquire. The pistol sight on AK is quicker. It is not much slower, but some fraction of a second. If I were to guess, maybe 1/5 to 1/4 second. Don't know if practice can overcome that.

My overall impression: I recommend it. Especially if you feel that you are not getting the accuracy potential of the AK (that's how I felt) and turned out I was right.

All things considered, I don't feel that Mojo is the best solution, but it is the ideal compromise. A really good sight would
be a peep sight a la AR-15, but it is not going to work on the AK well. You have to modify the receiver cover, and then it won't come off easily, and be expensive. So while not the best, it does indeed work better than the stock one, which is useless in my opinion.

I heard bad things about Williams site, mainly that it can break off the rifle. No idea if this is true.

Another good site,probably better than Mojo is the Krebs site. No experience with it either.

The Mojo sight appears as tough as the original.

Thanks for the report!
I looked hard at all three, the Mojo, Williams and Krebs peep sight for my SAR-1. In the end I decided the get the wiliiams, because it was only $23, and I wasn't sure how peep sight would work on an AKM. I just ordered it yesterday. I will post a report. They do not look as solid, but I may upgrade to the Krebs or Mojo later if I like it. I noticed the krebs is adjustable for elevation using the stock slider, and looks very authentic. I am glad to hear accuracy is improved over the blade sights, as that is one of my goals. I want to silence my pundit friends who say the AKM is an inherently inaccurate weapon!

Yes, do post a review.

A peep sight is the best upgrade you can make, I am convinced.

If you have an accurate AK, you are definitely not reaching the potential of it with the stock sights. Or even a mediocre AK.

The sights are a limiting factor. They are very quick but very inadequate for precison shooting. (Meaning 100 and beyond). My clone would not shot groups at 100, it would shoot patterns. I very occasionally got 3.5" groups. Most of the time, it was a huge disappointment. 6-9" groups. One time I got a 2.2" group and never again. It was just mocking me. I knew it could do better. Now I have proof.

I will report what it does at longer ranges. That would be most interesting.

Also, do try better ammo. Good domestic stuff like Win.