Yes looks a good lens. As an owner of a 100-400 II , previously a 150-500 Sigma, currently 300 II 2.8 and 600 F4 II, as good as the zoom lens are, there is a noticeable quality difference when you go for the big primes. They are just so sharp. Its why they can charge so much for them.
But you can still do great things with a lens like that 60-600mm . It's an amazing zoom lens range. Very useful.
Very enthusiastic review - the weakness of this type of lens (all the 150 - 600mm versions) tends to be at the long end (which is typically the length people buy them for), and this one is apparently very good in the middle (and acceptable at the edges even on FF) all the way out. Interesting option for those (eg birders) who need this length.