I will discuss the only downside to this lens first. The inability to accept a 'normal' filter, sure...you can make a set-up or even purchase an 'extreme' filter adaptor. But really?
If it were possible to stop the lens further then f/22 that would help, but it is what it is.
The positive side of this lens is the width! You get everything in landscape/nature. But it isn't f/1.2! So what, when was the last time anyone went out and took a landscape photo at that f-stop anyway? And this is the reason I purchased the lens....landscape. Too tight to get that 25mm lens? No problem for this one!
Would I recommend this one? Sure! Everyday of the week!
Will I be selling mine anytime soon? Don't hold your breath, I have a lot of shutters remaining on my Sony a7ii!
Did I mention this was made with full frame in mind? The DG series from Sigma is awesome on a budget!