Canon 85mm f2 macro IS vs Samyang 85mm f1.4

Francis A wrote:

With the canon coming in at 599 against samyang's 699 (B&H price), which one would you get?

I'm more interested in the RF85.  For me, I'm sure the 85/2 will provide plenty of subject separation from the background with nicely rendered out of focus areas. Some of the images I've seen look (albeit not full resolution) great.  Having the control ring on the RF lens would be more beneficial to me too - especially if I'm used to it on one lens (like the RF24-105/4), I don't have to change my shooting and dive into a menu or quick menu if I use the Canon but would with the Samyang.

The other reason I would pick the Canon over the Samyang is because I see to many conflicting reports on the Samyang and for some of the reviews it seems like I'd be stopping the lens to F2 at least anyway.

Here's 4 quotes from 4 different websites:

"Centre-sharpness isn’t overly impressive at f/1.4 but is rather better at f/2 and excellent from f/2.8 onwards. Edge- and corner-sharpness are comparatively poor."

"Sharpness is acceptable when shooting wide-open at f/1.4, very good at f/2 and outstanding from f/2.8 onwards, although the edges aren't quite as sharp as the centre, with f/2.8-f/11 producing the sharpest results."

"Central sharpness is excellent all the way from f/1.4 through to f/11. It is still very good at f/16. The edges are very good at f/1.4 and f/2, excellent from f/2.8 to f/8 and very good from f11 to f/16."

**Review of the Samyang AF 85/1.4 for EF** (I'm assuming the optical formula is the same)
"MTF (resolution) on the EOS 5Ds R (at 50 megapixels)
The Samyang AF 85mm f/1.4 EF is a lens with two souls. If you check the sample image section, you will notice that is dead sharp at near infinity settings. However, the performance isn't quite as good as shorter focus distances. Our test was performed from a distance of 3.5m. This is far from being a macro scenario and roughly equivalent to an upper body portrait taken with this. The drop of quality was already quite obvious as you can see in the charts below. The dead center quality is (just) very good at f/1.4 but the near center is already down to good quality here. The outer image field is soft. Stopping down to f/2 doesn't change much. There's a slight increase in quality at f/2.8. The peak performance is reached between f/4 and f/8. The broader center zone isn't bitingly sharp but certainly sufficient even for demanding users. The borders/corner remain just fair though. As usual, negative diffraction effects set in from f/11 onward.

For the sake of comparison with our legacy tests, we are supplying MTFs taken at 21 megapixels below. This is far from being as demanding as the MTFs based on a 50-megapixel sensor. Even so, the results aren't overly impressive compared to other prime lenses. The corner/border weakness remains at large aperture settings albeit it isn't quite as pronounced anymore. Stopping down shows the same gradual increase in quality. The center quality is excellent between f/4 and f/8 on this sensor and the outer image field is at least good to very good here."

People will have their own reasons for choosing either, you will need to prioritize what matters more.  And it might not be a bad idea to test them out first if you can, even if that means renting them (if that's possible).  Good luck.