From what I've read in this forum, it appears that bearing in mind security, cost and weight, OnGuard Bulldogs are the perfect choice. Alas, they appear not to be on sale in the UK, so my choices are limited to Kryptonite and Abus. The consensus appears to be that the Kryptonite New York 3000 is the way forward, but I've read very little about Abus locks on here (probably because most of you are American and Abus seems to restrict itself to Europe).
However, I'd still like to know whether the top-of-the-range Abus D-locks (the ones rated 15) are similar, more or less secure than the New York 3000, from what you regulars have read or had experience with. They're both hideously expensive (about £60, $120) but I'm prepared to spend this to stop my bike from getting stolen, of course.
Any insight, suggestions or recommendations much appreciated. Cheers.