I'm trying to decide whether I should go to the US for my PhD or stay in Europe. US would in my case mean better lab and more money, but I'm not sure I could cope with being away from my friends and family for five years or more. I know that only I can decide what's best for me, but any thoughts on this subject would be much appreciated.

Find out how much holiday you'll get, what hours you can expect to work and the average time to completion in the department you want to work in.

The time to completion for science PhDs in the UK is fixed by the research councils at between 3 and 4 years. In the US it can take much longer.

Yes, everyone has a home sickness and nobody wants to leave a sweet HOME but if you want to get somthing more than the rest people u should do that to achive new experience which would help you in future life, isn't it?