Dave, there is very good synergy between BAT preamps and amps. I own a Vk-60 and currently have a 30SE pre, but had a 3i when I got the 60. Though you can get good music by mixing brands, I think you'll be better served by BAT synergy. With your Hales, you definitely need the ss power of the vk-200. The 500 is mostly just a bigger 200, though it is dual mono, complete w/2 pc's needed. Good luck.
Steve
Steve