Hi Imagios
The trannys are MJL21193/4. The parts are certainly not boutique grade at that price but middle grade, all 1% MF resistors, MKPs and many 6.3 mm spade connections. Get a decent ratchet crimper unless you have a swage to suit or just mighty strong. The caps are as would be supplied in midrange commercial quality amps up to even $2,500 AU.
If you believe class A will be adversely affected by using such as Panasonic FC,M grade PSU caps, then replacing 6 x 10,000uF 50V will not be an obstacle for you.
I will say that distortion as low as claimed and without crossover artifacts is certainly distinct, dead quiet and genuinely the closest I have heard to studio production quality sound in the 20W design. If there is a problem, it is the specially wound toroid which is prone on some samples to a buzz at the constant 2.5 amps load which can be audible at close proximity. Resilient mounting has solved the problem for me in two builds.
The remote controlled preamp, incidentally, is buffered and amped with LM4562s which are amongst the very few opamps even in the running for the job.
I would not try to compare sonic qualities with any other amplifier as this is not a "musical" amp. However, if you need accuracy, IMHO, this is it for DIY. Frankly, I do like it very much because the imaging and soundstage is genuine, pin sharp, and absolutely stable. The rest is in the clarity to resolve massed voice sounds and and details that class AB generally struggles with. Try it with headphones, near field monitors or any decent, efficient speakers of 6 ohms and above and you will hear a difference to the rest....absolutely!
There are tweaks to the input pair balance, as mentioned here, which can make a significant improvement but its also impressive as it comes too. You will have to add your own little five button Philips RC5 code remocon and 230V power, however.