EF Lenses from UK or Overseas

Hi All,

I'm looking to get a new lens for my Canon eos 10d. I'm looking to get
something suitable for the odd Wedding or two as well as the usual
portraits, pets and landscape stuff. Unfortunately, the lens thing is still
pretty new to me and I'm not sure what would be my best option.

I've been looking at Canon and Sigma Lenses available at 7dayshop.com as
they seem to have the best UK prices.

Also, I have a brother in the USA who has offered to get me one over there
and bring it over with him when he visits but I'm a little (not a lot)
concerned about the warranty aspect, however, this would allow me to get
either a really good lens or one or two "average" lenses and take advantage
of the current exchange rate.

Any advice would be greatly appreciated.

Thanks

Jules