Well, essentially, it makes little difference where you do your trainng - except unless you listen to the salesmen! The biggest difference is that if you go for USA or other place with half reasonable weather, you will be a lot younger than if you muddle through with the restrictions that the UK wether puts upon you. Another advantage is that you will be financially less crippled and the finalajor advantage in training away from home is that it tends to focus your mind into training/studying hard since wasted time = wasted money in terms of living expenses.
There is plenty of anecdotal evidence of employers preferring UK trained pilots,
but, little in the way of hard evidence! Plenty of USA trained pilots join the right hand seat every year on equal pay and conditions to UK trained pilots.
Good luck!
