Macro lenses are intentionally designed to be optimized for close distances. It shouldn't be surprising that means compromise in performance at infinity.
Depends on what you mean by compromise. Soft corners, for instance, I cannot accept for landscapes. The corners at infinity of my EF 180 are mushy, no matter which aperture I use, even if "corner focused".
A slight drop of performance is usually the case with most macro lenses, and acceptable. What I need is kind of a universal lens, since I hate changing lenses when hiking in the mountains.
I must say I've been spoiled by my leica M and R macro lenses (M 4/90, R 2,8/60, R Apo 2,8/100). All three are tack-sharp even in the corners. This is why, after having heard so much praise about the RF 100 L, I hope it will produce excellent results at infinity too!
The only trouble with the Leica 100 Apo being the lack of AF, otherwise...