Pannier bag for laptop

Looking for a good pannier bag that protects a laptop well (or as well as a pannier bag can). Also want enough room in it for lunch and a change of clothes. Given that the laptop is worth $3k, I’m not too fussed about the cost of the bag itself. Being able to also use it as a back-pack or courier bag would be good.

I use an Altura Dryline laptop pannier on one side and a standard Dryline pannier on the other.

No rucksack feature, but I have managed to drop the pannier on to tarmac and the laptop was absolutely fine. Also ridden an hour in driving rain (the sort where you can’t see the road or the bottom of your wheels – I was going home so had no choice) and the laptop pannier didn’t leak – the standard Dryline leaked a little but not much considering.

How about these with a bit more room.

http://ortlieb.de/_prod.php?lang=en&produkt=officebag_bnw&biketoy=rear

http://ortlieb.de/_prod.php?lang=en&produkt=downtown&biketoy=rear

I use Ortlieb normal rear panniers and just put my laptop in a padded insert and has been fine for years.

I’ve got one of these – http://www.carradice.co.uk/index.php?page_id=product&product_id=64

I bought mine S/H and don’t have the laptop sleeve but it’s really sturdy and well made even if a little old fashioned looking. The straps have plenty of adjustment and you can hold a surprising amount of stuff in it. Comes with a shoulder strap so you can use it as a messenger bag

I’ve got a New Looxs Mondi
http://www.halfords.com/cycling/accessories/panniers-racks/new-looxs-mondi-single-bike-pannier-in-black
Works a treat for my 15″ Dell M3800. Survves the 22 mile commute happily and looks good off the bike.

17″ Dell Precision behemoth here.
Lives in a neoprene sleeve, sits on a “nest” of foam padding at the bottom of a normal pannier, with my folded shirt & trousers in front of it.

Swap the drive for a solid state one if possible.
No issues in a few years, through plenty of rain in that time.

I use a peli laptop briefcase – which is waterproof, dustproof and crushproof, and some custom hooks to fix to the pannier rack. It’s bombproof, but a bit heavy. I could probably crash full speed and it’d be fine. For a £3k laptop I don’t think I’d risk anything less when on the bike. Mine’s worth a lot less than that!

I got mine from timbuk2 and its een bombproof and protective so far!