It's been a while since I bought/sold lenses as I almost had my perfect setup.
When Canon released the 16-35 f4L IS I felt the UWA shortage was only temporary solved.
But this was the well known 'commercial Canon trap', releasing first a perfect f4 and later only a f2.8 III to sell more lenses.
Some (like me) couldn't keep waiting and bought the f4 temporary, awaiting an affordable sharp f2.8 uwa.
F2.8 is always better (I shoot a lot in dark circumstances, startrails,...)
Now I'm starting to appreciate more and more speciality lenses, the cheaper alternative brands are helping to solve the uwa (affordable) shortage.
Some collect a bit dust, but when you screw them on it's directly 'wow'.
On the wide i'm considering selling my 16-35f4L IS + Tamron 24-70 2.8VC and replacing them with :
-Venus Optics 12 f2.8 Zero D (out this summer)
-Samyang/Rokinon 12 f2.8 fisheye
-Sigma 35 1.4 Art (back again)
The FOV / fastness seems a lot more exciting than my mainstream standardzooms.
I won't buy the Samyang/Rokinon 14 2.8 with moustache distortion as the Venus optics will kill this one soon.
The Venus Optics 12 2.8 on FF will be a lot wider (crops possible if necessary) and I prefer compact lighter primes.
This will be my future base lens, as I use a UWA 80% for dark urban locations.
I would use the fisheye for partyphotograpy or some wow shots of special architecture.
I could also buy the Samyang/Rokinon and defish, but that would be extra work again and probably not the same.
So unexpectedly i'm waiting for Venus Optics to change my wide setup.
Probably after the summer when it hits the market in Europe...
Not much people know this brand (I didn't know it either at first), just like the "Irix" brand which also has some uwa's.
I never thought I would switch to manual focus lenses, but time has come after seeing those samples