Passenger seat bag - flavor of the day? Kriega 30 or...?

[Jack_the_Lad]

Going on a solo long-ish trip in a couple of weeks and thought that a decent bag for the passenger seat would be a good idea.

The Kriega looks good (if not inexpensive), and I've had great experiences with their other gear.

Any thoughts for or against the 30L bag? Alternatives?

(Before anyone suggests tank bags and top boxes, I have both, so am interested solely in a passenger seat bag, in part as I can use it on other bikes)