Last winter I buy several BLI mikado's, several because I want class of locomotives for my Maclau River in Nscale
The best comparative was the aging heavy mikado from Kato
I don't speak about sound since the Kato one didn't have it but BLI or the Kato ones are extremly fine runner with excellent slow speed control under DCC ( Zimo in my case)
In conclusion excellent running locomotives with very fine details
Hope to see more steamer from BLI and hope may be to see a Class A and a YB 6 from the N&W which are offered in HO by BLI.
I really like them. I think they look great, run great, and sound great (at least as good as you can in N-scale). When you have the sound off they're not as quite as Atlas or Kato, but they're not bad, certainly not loud, just not whisper quite(I wonder if the new Paragon 4 decoder helps in this regard, the ones I have are Paragon 2 and 3). As far as I know, they are the only N-scale locos you can get from the factory with working ditch lights, not just lit, but working, as in alternatly flashing when you blow the horn, and cab a cab light.
This would be my first sojourn into sound locomoives and I am thinking about purchasing a BLI N scale AC6000. I have never had a BLI locomotive and would like to know how do they look, how well do they run and how good is the sound