Probably still worth it for a mac. And the ‘warranty’ and AppleCare are applicable worldwide. I wouldn’t bother with other brands as they are usually competitive in pricing over here. Try googling a few models & compare though. I thought Circuit City filed for chapter 11 a couple of years back. Best Buy are still going and as molgrips says they are interested in customers and have a clue about competitive pricing and their products. They’re worth going into just to see the difference in range, knowledge and pricing. BTW, there’s a best buy in southampton, england.
One thing to be aware of: sales tax. Some places have so many sales taxes that what looked like a nice price on the shelf turns into nothing special at the till. Again, you can check this out on line. You can get state sales tax, county sales tax, city sales tax… You’re not going to Delaware (first state of the union) are you? No sales tax there.