Vantaggi
Although the compensation is lacking due to payscale and currency exchange rates from the UK to the US, VisitBritain does a good job to make up for it with the benefits offered. Great Medical, Dental, and Vision plans, generous vacation time, and paid holidays, etc. are usually the big draws however, for some the relaxed dress code (and sometimes seemingly friendly work environment), and other incentives seal the deal.
Svantaggi
The competitive environment at headquarters is often to blame for the passive-aggressive and fear-driven environment in the US locations. I'm not sure if it's the culture difference between HQ and here in the US but it makes for an underlying lack of trust with superiors and colleagues, not to mention drives miscommunication which often leads to other issues behind the scenes. The lack of career advancement also contributes to the large turnover with employees globally, so if you are interested in growing with the company, it can happen but I wouldn't rely on that being an option.