why poweball is cheaper on other websites?

[llegisa]

We always talk about cheap imitations, but what about the same designed Powerball 250Hz Pro on other websites. I found one of them for 20$ from UK.
Can I trust them? They give lifetime warranty as well. I just want to know if this site (powerballs.com) is the only one that sells original Powerballs or there are more of them?
Thank you very much!

I'm talking about this site (don't know if I can post links): http://www.lovepowerball.co.uk/cart.php?page=12&offset=

[llegisa]

doesn't matter, I bought the original powerball from this site.