Yep Zen are ace thats who we have our buisness package with. Never had any big issues, good customer service.
Southwell 1.1mile should get you about 6meg easy unless its a really busy day, i'd be surprised if anyone on a domestic account could get 8meg even if they were next door to the exchange, the connection ratios would still bring it down.
If had the option at the mo to go with virgin then i would at the drop of a hat, my folks have it and its bloody great all day long..
if you want to test your broadband use the speed checker at
www.thinkbroadband.com pretty accurate from what i can tell.