VTL MB 185 SERIES II

I have used VTL Amps for 20 years.  The auto biasing and fault protection is truly an awesome feature.

I own vtl  250 mono blocks for over 15 years , sound wise very good. Biasing them not that hard .  8 ,6550 tubes in each amp enough power for most speakers ,  rated at 230 watts each.

I have the MB-185 series 1.
They are incredible in tetrode in my system.

If they’re not good in your system in tetrode, you have something wrong.

It is also no problem to bias them.
If you have a multimeter & a screwdriver, it’s really simple.

would agree with @vegasears , the new auto bias VTL amps are really nice and pretty trouble free. 

Before the 450MKII were purchased I had VTL 300 Deluxe mono blocks.  Great amps but tube faults were a major pain.  With the 450's tube faults are a breeze.  When a tube goes, it's identified by a flashing little green light.  The power to the amp is shut, with gloves the tube is replaced, if a fuse went its also replaced.  I'm up and running in less the 5 minutes.  Auto Biasing between the notes of the music, come on now that's too cool.