Arthur will roast me for this...we already had this discussion on the RT board
I bought Spieglers for my RT when the OEM lines blew, and they were very helpful. I called on a Thursday, and they made up a set same-day, and shipped them to me 2nd day air, with Saturday deliver. Had UPS not....made love to the pooch, I would've gotten them in that same weekend.
It's true that you may experience a bit of grief with fit in some areas, as Spieglers cuts their lines to be the -exact- same length as the OEM lines. Braided SS is a lot less flexible in small-radius bends, so it's a bit more work getting the lines coaxed into the same shape as the flexy rubber lines that are stock. When I called Spieglers to give feedback after my install, they said they are aware that this causes some woe, but also that they've had several conversations directly with BMW Motorrad, and that BMW insists that aftermarket lines must be cut to the same length and configuration as the OEM lines in order for brakes to function properly, warranties not to be voided, etc etc etc.
As for the installation, it's pretty easy if you go one line at a time...that is, remove one stock line, find the new SS line that matches length and fitting configuration/bend, and install the new line with the new washers (and your old banjo bolt, unless you've bought new ones).
The plastic adapter they provide to twist the fittings' configuration worked OK for me...but eventually gave out about 3/4 of the way through the install. The adapter has some little plastic teeth on it, which just aren't up to the task of 10-12 adjustments. A bit annoying, but not a show-stopper.
All in all, I was happy that Speiglers helped me out (they generally make their kits to-order, as there are a ton of different configurations/colors they offer) quickly, and the kit worked well. You may find that the kit is not an absolutely perfect drop-in, and that some minor fitting is required. However, I don't know that this is totally unexpected from any manufacturer that doesn't only make parts for BMWs.
In any case, good luck on the search. If you do go the route of Spieglers, they're one of the few you can call directly (instead to having to go to a distributor), and order/purchase product.