There are a lot of factors in the “latency” of pulling up web sites, including how well your own ISP is connected or its peering connections with other major providers stretching across the Atlantic (or Pacific for our client base in Australia, Japan, etc.). While we have a rather nice sized base of clients in Europe and Asia, and we do detailed monitoring using multiple 3rd party monitoring company’s, with monitoring locations globally, its not practical of course to monitor the endless collections of ISPs and routes packets can take.
While the idea of building out a similar infrastructure as we have here, in Europe, has some appeal, its a major undertaking, will cost at a minimum of several hundred thousand dollars to start, not counting hiring of staff. Based on our focus and business model would also require two locations as a primary and a disaster recovery/off-site backup location too, as long distance fiber across the Atlantic to one of our existing US locations is cost prohibitive at best for an operation of our size. Currently the investment costs would be higher still because of the weak US dollar compared to the Euro, and the return on investment time really does not make it a practical option at this time for us.
In all honesty though, looking at the number of happy European based clients, many of which we have had for many years, I am not sure the latency issues are typical enough for us to venture down that road in the near future.
Something to consider for your actual large file (flash, video, audio files) would be to off-load those to Amazon S3 storage, setup a sub-domain like media.yourdomain.com and use the Amazon S3 European location. This would provide a closer repository for large static content with a respected company, and leave the dynamic content to be powered from our infrastructure as you currently are doing. Amazon S3 Scroll down to the Europe pricing for storage and bandwidth costs. It could at least be worth a test run to see if that assists in what you are seeing, though I would be curious to see if others in Europe are seeing what you are when hitting the site you mentioned above.
Let me know if you have any questions, and feel free to private message me as well here in the forums.