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

Absolutely!  QS amps, are quiet, reliable, easy to mod or repair if needed.  I run my mid monos every day for 8-10 hours and they just work.  Spend some $ on some good small signal tubes and a couple of decent power cords and you’ve got great sounding reliable amps. 

I have a pair of V-4 Monoblocs at 120 watts per channel. They use KT-88's 4 per side. Sound great imaging and the instruments are awesome.

I recently purchased KT mono with KT150 which produces 100WPC. It took three and half months to get it. Ordered in mid Oct and received in early February. The problem was, they did not have transformers to build amps. 

Their serial number is 1 and 2. How often do you purchase an equipment with serial number 1?

I also have Plinius SA102 (upgraded from Galbo). My preamp is Audible Illusions M3B. I have two pairs of speakers: Gershman Grand Avant Garde and Tyler Linbrook systems (one piece). SA102 sounds beautiful with Gershman but Linbrook sounds much inferior. However, with KT mono, Linbrook sounds much better, but Gershman sounds a bit less dynamic and less bass with KT mono compared with Plinius.

It might be because Gershman is power hungry. The differences may be expected from a solid state amp and a tube amp. Overall, I've realized that Linbrook has more potential with different setup, and Plinius works very well with Gershman. 

Somehow I hoped QS KT mono would blow away Plinius in every aspect, but it was not a realistic expectation. Plinius SA102 with upgrade can compete well with any solid amps at around 10K, and I cannot possibly expect a tube amp at under 4K would outperform. 

Overall, I am satisfied with the purchase. KT mono is paired with LInbrook and Plinius is paired with Gershman. With two outputs from M3B, I can easily enjoy both tube and solid state amps without cable changes with the same sources -- OPPO 105 for digital and my analog sources (Ortofon SPUs and MC20 super, Denon 103r, AT150mlx, ...).

The answer is no if value your resale investment. Audioresearch and VAC will hold their value much better than quicksilver.

@ihcho are you running the 4 or 8 ohm speaker taps on the back of the QS Monos --

• 8 or 4...with your 4ohm 90db Tyler speakers?
• 8 or 4...with your 6ohm 87db Gershman speakers?
• what preamp are you using to drive the QS monos?

A 3db speaker sensitivity difference there worth noting. Other things to check.  

FYI, a member on another forum was having unsolved headaches driving his 87db Gershman Grands’ with his powerful Bryston 14B amp (600w@8ohm / 900@4ohms). At first everyone thought it was a preamp gain / output voltage issue not able to drive the amp(s). As it turned out, he had his amps and gear all plugged into the same AC wall plug / circuit. To fix it, Installed two dedicated 20amp circuits, problem solved, amp was able to drive the Gershams Grands ok. 1) Check, try the 4ohm taps on the Monos if you have not done so yet. And, 2) try plugging QS monos in to a different wall plug not on the same circuit as the rest of your gear. Best of luck.