I use mine with Bergantino HS410. Works great. The wide low end of the WA complements the tight bottom of the berg.
I also tried it with the 8 ohm 1x15 on the bottom of the 410 with total 2,6 ohm or something and it was massive!
On the front of the Walkabout I use EBS Multicomp. Probably worth mentioning that I have gain on the Multicomp set more than unity gain, so it sends quite hot signal to the Walkabout. Still not distorting the tubes, though.
With five-piece band and HS410 I was never over the noon at the master volume, usually at about 10-11 o'clock, with WA gain at 11.
