I've had some good ones and enjoyed each of them immensely. Integrateds at various price points and for specific purposes i.e.:system matching, in no particular order: McIntosh MA2275 (not awesome), BAT VK300X SE (very good), Cary SLI80 F1 (twice, lush and euphonic depending on tubes), Naim Supernait (not bad, punchy but a little grainy at times), Shindo Apetite (very cool with the right speakers, trumped Leben et al), VAC Sigma 160i (incredibly rich and detailed, more versatile than any other tube integrated I've owned) and a Nagra 300i (OMG, nothing I've heard even comes close!!!). I've demoed ASR, Boulder, Mcintosh solid state, etc.
BUT....there is no best.
BUT....there is no best.