Well, now not so sure about AO. Just went there to order and I found, contrary to reports upthread ^^, that they do not deliver free within 24 hours, they do not take your old machine away for free, and they do not unpack your new machine and take away the packaging for free.
These services are charged as follows:
24 hour delivery - £19.99
Recycle old machine - £19.99
Unpack and take away packaging - £2.49.
So that is a whopping additional £42.46 to pay
.
Yes, there is a standard delivery option which is free, but the earliest date is Thursday, which is very good, but disappointing when I'd thought it would be 24 hours 
JL, on the other hand, offer free delivery - within 7 working days on their own brand - and they take the old machine away for £9.
What is curious, however, is that I have discovered from the reviews that the JL washer/dryer is a re-badged AEG. Now I'm bewildered: the JL is rated by Which as 89% reliable, 2nd in the list, while AEG comes in at 6th with 74% reliability
. Given that Which draw their results from user reports, I suspect there could be a bit of brand snobbery creeping in there!