I have learned a TON in the last few years, by:
1) My own research;
2) Asking (limited) questions to the experts, like the great people on here, who are literally a wealth of knowledge;
3) My own constant research;
4) Buying every book I can get my hands on, like Vince Malta's book;
5) Doing hours and hours of my own research.
When I look at a potential bat like that, the first thing I do is google exemplars that are known to be "legit".
Make sure the model is correct for the time period. I see a lot of these on ebay that are clearly wrong; although Ben is correct, a lot of time, the sellers have no idea what they are selling. I bought a Yaz bat from a guy who said it was just a pro stock, and it turned out to be a gamer (and I got a PSA letter for it, so it wasn't just my opinion). Another guy swore it was a Judge gamer, but no one believed him. I did my research, and he was
right (and now it is my bat, with a PSA letter).
In your case, I did find an exemplar with "M356" on the knob with a quick search, so I conclude that is a good sign. It would be nice if you could see the stamping on the knob though.
I would not call that one "game used", I think the experts say "game ready".
Big price difference between the two.
A lot of times, if it has use, there might be a distinct use pattern. You would have to research that for each player.
I used to collect cards, but now I am almost exclusively a bat guy (also a jersey from time to time). It is amazing to hold a bat that your childhood hero once actually used, and often, you can get one for the same price as one of those green/limited number/serialized/atomic refractor card thingys.
