Are Quicksilver power tube amps in the same league as VAC, VTL, BAT, ARC, ...?

My Mid Monos sound wonderful and are very reliable. I have owned ARC and Cary tubed power amps and they are easily in the same league soundwise.  If you need more power consider the V4. The capability to use different output tubes which both the V4 and the Mid Monos is great.  I prefer the sound of EL34 tubes to 6550/KT88s but you can use either in these amps as per your liking. 
BTW, The mid monos at 40W/channel drive my 89db speakers to more than adequate level and play as loud as the 100WPC solid state Belles Power Amp  I was using before. Tube watts seem more powerful and satisfying to me than solid state watts. I see there are some used  Quickliver 80w monblocks for sale at Echo Audio.

About five years ago I compared the mono 120s with the ARC 150 and I thought it was a tossup. The Quicksilver’s weren’t just good for the money, they were just as good.

yes.  and no

Purchased my Quicksilver Minimite Monoblocks  new and have owned them since 2006. I consider them to be some of the best sounding power amplifiers I have ever heard.  

Regarding their design, they are simplicity itself, using point to point wiring and quality transformers. Mike Sanders is also one of the most honest people in this business, and stands by his products.

I love my Horn Monos.  Quicksilver doesn’t play the “review game”, so he’s not sending out amps for free in return for good press.  Instead he relies on word of mouth.  I will say this; back in the day, Quicksilver was a darling of both TAS and Stereophile and reviewed very favorably against all the “giants” of the industry.