I've worked abroad, the longest was for 6 months at a relatively early point in my career. . Since then, I've spent small amounts of time working abroad. Usually for a few weeks at a time.
Did working abroad progress your career faster than what would have occurred if you had stayed in the UK?
The 6 months really helped me, the company's board was based in France and I was working in the head office. The MD of the UK business unit came over every two weeks and was always looking for someone to drink with, as I was the only other English person there, I boozed with him every two weeks for 6 months. It helped me a lot.
I've seen it have varying impacts on careers.
Will you be working abroad, but still have your contract of employment with the UK entity? Where will your performance review take place?
I've seen people work abroad for long periods of time and only get average performance reviews because their work is not well known or it's seen that it's easier to succeed in the other geography. i.e. if you're working in London and go to pretty much anywhere else, people (rightly or wrongly) will assume it's not as high profile etc etc.
Does having a foreign project add much to your CV or do future employers focus on the project and the skills used regardless of location?
It really depends on what the requirement of your future employer is. The positions I interview for often require an element of international travel, if you had some decent experience here, then it would be a positive thing. However, if the job was doing some data analysis in London then international experience would not be important.
Are there any negatives you have found from working abroad?
What happens if you need to get back to the UK quickly? Will your company support you in this?
The other negative, which is not applicable in your case, is spending large amounts of time away from the wife and family.
I've always worked in interesting places when working abroad, but you could in theory go to some right dodgy places.
Any tips anyone has about working abroad?
Commit to learning the language. Ask, or make it a condition, your employer to pay for lessons.
Find the local English pub, I found that girls who a) liked English men b) wanted to practice their English would go.
Put yourself out there - otherwise you could be in for a lonely experience.
Would you recommend doing it?