That is a really good question, but not one very easy to answer. It's a case of being able to walk in your shoes. What's important to you? Lifestyle isn't really a case of fitting to one's income in a like-for-like comparison, more of what you can live with and what you can't live without.
One silly example, but it might help to get across my point:
- McDonald's. In my view, they seem to take the US price, and translate it to be about the same worth as the UK price.
- Burger King. I might be wrong, but they seem to take the price of the US burger and simply take off the dollar sign, then slap on a pound sign. (I KNOW Hooters did this when they were around a few years back...they didn't last, BTW.) By doing so, it makes the price of a Burger King burger almost double in the UK than in the US.
So, are you a McDonald's person, or a Burger King fan?
(rhetorical question: my question really has nothing to do with whether you even go for fast food, so please everyone, don't veer off the purpose of this thread...just making food for thought, okay?)
Where you live certainly makes a difference. London prices are certainly higher for day-to-day services than they are here in Wiltshire, where I live. Restaurant prices higher, but you might get a better cut of meat, too. Hairdressers are more expensive, but I might spend money on transportation to London for a haircut just because it would be better.
My own personal take is that you'll do great on 20-30k in the UK in general, perhaps not as well in the London area. But, unless you're bringing some collateral for downpayment with you, it may take a while to break onto the poperty ladder. But get on with everyday things and have enough left over for a treat, yes, I think it's do-able.
Now, about that career...I LOVE the fact that I live in a country with so much opportunity to be heard. You will have access to some pretty great resources and influential people. Far more easy to be seen here than in a relatively faceless US, where there is a lot of competition for the same position.
These are just my own thoughts and gut feelings. Check out a site that will give you more of the facts and statistics about Watford, specifically:
Up My Street - Watford