This is clearly a good quality product from a well known company.
I like the fact that it folds and has a pocket clip - it makes it convenient to carry and have available when you need it. The bright yellow colour is a definite bonus - if like me you often find yourself putting down a tool while working and then looking around thinking "where did I put that?".
It is comfortable to hold and use, and it is handy that you can stotre up to 3 blades in the handle.
However, it comes without any clear instructions (the graphics on the back of the card are not particularly clear). I am ana engineer and consider myself quite practical, but it took me a little while to figure out exactly how the knnife worked - eg how to unlock it to close it.
I found it VERY fiddly to insert a new blade, and successfully locate it in place. It took me many attempts to successfully locate it such that it would fully retract. In fact I started to wonder if I was doing it correctly.
In common with all other Stanley reetractable knives, the blade does have a certain amount of "play" when in use. Depending on the exact task that you are carrying it this can be a little annoying.
I actually also own a couuple of these: Rolson Tools 62845 Folding Lock-Back Utility Knife
They are not quite as ergonomic/comfortable-to use as the FatMax, but the blade is held complettely immobile.
I think I will probabnly use the Fatmax for general use, but the Rolson when I need to cut precisely/accurately.