Pros
Co-workers were friendly and technically competent (but that's irrelevant now, since all of them left within 2 years).
Cons
I have to say, the analysis from the author of the other 1-star glassdoor review is spot on.
I've left with the same analysis as the author of the other 1-star review.
The owner/CEO is a narcissistic gaslighter who is hilariously incompetent.
If you're taking the job, know that he takes great enjoyment out of belittling people, and telling people how they should improve themselves.
Subject of your improvement can be any abstract aspect of your personal life, your personality or how you deal with things (even psychological / medical matters). Obviously, it is all deliberately packaged as 'sincere' advice and 'openness'.
It is incredibly hilarious if you're able to take a couple of steps back. Because the CEO has big troubles with basic tasks and has SERIOUS conflicts with every single person and organization people need to deal with. This includes: clients, banks, suppliers, authorities, employees etc. You can be sure to be risking YOUR reputation with those organizations due to (in)actions of this employer.
You'll be hearing stories about how he's a victim of great misfortune, but over time the true cause will become apparent to you.
Colleagues in the Hungary office weren't paid for almost a full year. Working without any salary, just monthly promises. Eventually that got settled but it still caused big troubles. The tiniest bit of reciprocity or honest empathy about the (in)direct damage inflicted on others is completely non-existent.
If it wasn't for those motivated, fresh-out-of-uni employees, this company would've gone down years ago already.
If you decide to accept the job, at least clearly set your boundaries, from day one. Don't take anything -positive or negative- coming out of this guy's mouth seriously. Don't let a fool tell you how you should be doing things.
Finishing off with something positive: his strong points are sales and marketing indeed, but that's it.