I like that it is very easy to use, even if you are not technical at all! It's also great because of how customizable everything can be from colors/themes etc., so there isn't much left out when building your site with this product (which makes sense since they're doing such an awesome job).
There aren’t any cons really - but maybe some more features would help? Maybe include analytics as well or something along those lines could make things better in terms of customization options available. We've used other loggers before which were too complicated compared to timber where we have been able customize our logs easily without having tons of plugins installed just by using their API tools themselves; plus being simple yet powerful enough was quite nice about them overall.