I've heard the VK-600SE($11,300 list) in a dealer's tweaked soundroom, thru $35K speakers, 20K front end, etc. I was pretty impressed after it warmed up (45 minutes). I've heard the DNA-500($7K list) in my own system, thru Legacy WHispers, Sunfire TGIV, elrod sig cords, BPT 3.5 Sig Plus, and I liked the DNA-500 better, so I bought it. It is very difficult to find a dealer who carries both these brands.
They are both involving amps, with excellent midrange presentation. I did not hear them thru identical systems, and I'll be pretty surprised if you find anyone who has, but you never know, I guess. I thought the DNA-500 was more musical and accurate, especially in the bass area, with a deeper soundstage, while the 600 had a wider soundstage. That's just how they sounded to me. The BAT is also taller, deeper, heavier and throws more heat, which may or may not be a factor for you.
I don't think you can go wrong with either of these amps, but you need to hear them for yourself in order to decide which sounds better to you, in your system. Asking people which they think is better is going to be largely system dependent as well as personal preference.
They are both involving amps, with excellent midrange presentation. I did not hear them thru identical systems, and I'll be pretty surprised if you find anyone who has, but you never know, I guess. I thought the DNA-500 was more musical and accurate, especially in the bass area, with a deeper soundstage, while the 600 had a wider soundstage. That's just how they sounded to me. The BAT is also taller, deeper, heavier and throws more heat, which may or may not be a factor for you.
I don't think you can go wrong with either of these amps, but you need to hear them for yourself in order to decide which sounds better to you, in your system. Asking people which they think is better is going to be largely system dependent as well as personal preference.