"If a non Pentaxian asks me it would be really difficult to say that a Pentax 55-300 lens is equal to a Tamron 150-600 when it comes to reach and AF-speed."
AF speed, yes, absolutely. Carrying weight, the Pentax will kill it. It all depends on what you value. Other people say the K-3iii is right up there with D500s.
Stick to what you know, accept others may know more, an we'll aways be happy. Claiming you know what's best for everyone and only your opinion matters , not acceptable.
"Tell them to buy an expensive Pentax til next lesson?"
Let them handle one of yours to see what they think. I assume you're having to advertise for students and where ever you teach has no demonstration cameras for students to try out. I was in a different situation. We didn't ask students to use thier own cameras for classroom assignments.
Quote: I can not sell my Pentax gear at a resonable price so I am stuck with it.
And yet for some of us, we shoot Pentax because it best suits our needs. everyone is different.
Looking in the Camera Canada - cameras, what's available, cheapest first.
Canon M200 with 15-45mm Lens Black-24 MP ---currently on sale, but regular price $779
Sony A6 with 16-50 24 MP- $779
Pentax K-70 with 18-50 regular $899
The Cheapest Nikon they list Z30 Digital Camera Body- 20 MP- with 16-50 $999 on sale.
It's fine if you want to make price the issue, as long as you don't confuse Swedish prices, with the rest of the forums. You kinda limited you audience there.