I worked at JPM in Luxembourg for 5 years and I enjoyed my time over there.
Work/Life Balance is not the best, you must be ready to be flexible and not to be afraid of overtime.
Management was very supportive and was among the best compared to the other places I worked for in Luxembourg.
Salary was okay, not marvelous but not too bad either.
If you show your willingness to succeed, that you comply with the company culture and demonstrate good relationship skills, you may be rewarded of your efforts.
The only cons would concern internal mobility. Looks like only the worse team members get such opportunity. When you are too good and get bored in your job, and if no promotion opportunities seem to show up, it will be time to resign.
Their social committee is deeply committed in making JPM Lux a better place to work at.
Company culture, management
Wages (a bit low), lack of internal mobility