Well that's definitely weird..as you describe it. Those are all really different manual of arms. I'm a proponent to sticking to one gun that you train a lot with. I've carried a couple different guns myself. Usually going from Glock to SIG to Glock to 1911 to SIG to Glock and stuck at Glock.
Hope you kept up.
But to carry a different gun all the time? I have to question where his mindset is.
Probably just showcasing. Loves guns. Maybe loves guns but doesn't train.
Like a car collector that doesn't drive all the cars, just has them. If that's his thing I won't judge him. That's not my thing though.