Question regarding Circular Polarizer

[Anirban Halder]

I've an amateurish question regarding usage of circular polarizer filter. Whenever I've used Nikon CPL on my 18-200 mm zoom (with D200), I was satisfied with the results. The Nikon samples (example below) doesn't look dull or flat to my eyes (or may be they do, tell me please if you feel they are dull).
But when I used BW polarizer on Fuji 18-55 zoom (with X-T10), I did not get same results. The photos looked fairly dull and flat.

Questions:
- Does the Fuji results below look different because of polarizer or because general light conditions were different?
Do the results/effect vary depending upon which system you are using? (DSLR vs Mirrorless)
- I can go out and click more shots to compare side-by-side. But I’m curious to know what your experience have been with CPL filter.
 

[Frank Fremerey]

Different scene contrast is what comes to mind first. Camera and Filter seem innocent.

First one looks like Greek summer light at midday. Second one is hazy late afternoon possibly autumnal

[atpaula]

Sorry no experience with mirrorless.
Your pictures seem fine to me.
I´ve been using polarizing filters (cpl now) for more than 30 years because I like the result they provide.
They are supposed to provide rich and vibrant colors because they remove reflections. I don´t call it dull. I call it beautiful colors, like in your first pic.

[Jakov Minić]

Anirban, why don't you make the same photo with and without the circular polarizer?
You will know immediately which is to you liking
I used to use polarizers a lot. I don't have a valid reason why I stopped...

[BEZ]

I used to use polarizers a lot. I don't have a valid reason why I stopped...

Photoshop! 

Cheers

[Anirban Halder]

Thank you everyone for your valuable comments.

Anirban, why don't you make the same photo with and without the circular polarizer?
You will know immediately which is to you liking

I'm too lazy for that, Jakov.  Jokes apart, I will certainly do that. I always forget about it, but now I will remember, hopefully.

[rosko]

I second Jakov in his relevant answer.

I use pola filters only to enhance cloudy landscapes and to eliminate any glass or water reflections.

[pluton]

You'll have to shoot exact A-B tests* to know if the hypothesis has value.  I suspect that if you did test side-by-side, you'd see no difference that could blamed on the CPL filter.  Greek daylight is famously contrasty, and San Francisco is equally famous for having a marine-influenced atmosphere.
*Same scene, same time, same angle of view.

[Anirban Halder]

Thanks Francis, Keith. Point taken.