They’re low-end Chinese products that are similar to Farmertec...
We have tried a few. Four years ago we had some success with the 1127 ms290 cylinders. Since then, I don’t trust ‘em. We had one Husky? Kit that had a hole right through the casting... just noticed it before install.
The ports are usually rough and the plating is weak- my shop used to just install ‘em on customer’s saws if they wanted a cheap fix. Now they offer Hyway and Meteor.
The rings were weak as per usual with AM kits. The pistons passed the eye test but weren’t the best castings.
I wouldn’t use ‘em for anything more than a personal spare firewood saw.