I have some Snap-on, lots of Williams, lots of SK, lots of Mac and Lots of Proto, Im not a professional Mechanic, but I do wrench and have for many many years. As far as quality of the wrench is concerned I can't tell a big difference between any of the above mentioned wrenches, but I will say the feel of a snap-on wrench (especially) a set of snap- on box end wrenches I have, is great. For me when I pick up a Snap on wrench I can tell, It just feels right in my hand
All of my wrenches/sockets ratchets are old, very old so they are probably pretty much different from wrenches you buy today.