I spend considerable amounts of time in both countries.
In Poland I pretty much get the advertized speeds, maybe it's slightly slower in peek hours. Currently I'm connected via cable - 6 Mbps and yesterday's episode of House is coming home almost that fast.
I've lived in two different houses in UK over the past 1.5 years and used the web at friend's house numerous times. Every house had DSL connection (speeds between 6 and 10 Mbps) from different providers. It's decent during the day (I'd say ~3 Mbps), but once everyone comes back home from school/work (~5p.m.) speeds drop to below 512 kbps (web, anything out of the standard ports range drops to a crawl).
Google is your friend. From the meta description tag of netcraft.com:
"Netcraft provide monthly Internet research reports on the apparent death of FreeBSD."
All seems condemned in the long run to approximate a state akin to Gaussian noise. -- James Martin