I go a few times a year for work (when you say 'UK firm', do you mean a law firm?). As lots of people have already said, it is stupidly expensive – half-decent business hotels basically start at £250 per night. The food is also terrible, the roads are shocking and the people can be quite aggressive. Despite that, I love it. Having local friends helps if you want to properly scratch beneath the surface, but once you do it's a really fun place to be. It does get stupidly cold in winter, but as Grum says it's somehow less depressing than UK winters as it's not as windy all the time.
That said, I'd be reluctant to work or live there, depending on the field. While it's come a long way from the days of the 'Wild East', it can still be a pretty dangerous place to do business.