Yondering, I am inclined to ask you to list them, it would not be the first time a technician was wrong at a vendor. That said would you buy a Gen 2 glock for $350 over a new Gen 4 for $560 plus tax? If there is a major plus for the Gen 4 I would like to understand it.
Personally, I'd take the Gen4 every time. For the most part the changes are all improvements. Some guys still like to bring up the reliability issues of early gen4 guns, but that doesn't mean much; most products tend to have issues with early samples, and we aren't in that time frame any more on these.
Some of the different parts:
- Recoil spring
- Barrel (larger cutout for recoil spring)
- Ejector housing (different shape/angle for smaller gen4 grip)
- Mag release
- Locking block material/manufacturing.
I don't remember if the 2 pin to 3 pin change was gen 1 to gen 2, or gen 2.5?
Along with the different ejector housing, Glock installs a different connector in the gen4 to account for the different angle. Obviously the connector is interchangeable with older guns, but is still another different part from the factory.
The internal function is still the same, even though some parts have changed; maybe that's what the tech was trying to say.
