Thus far, I am totally enamored with the Esoteric. I have about 50 hours on it. I really can't find any shortcomings at all. It is noticeably better than the Accuphase E-470 on all counts - especially the warmth which reminds me of my Class A gear I used to own. It has plenty of power and all the features one could ask for. Apparently much of the technology for this amp has trickled down from the Grandioso line. There are lots of programming options as well (naming sources etc.). Build quality is superb. For those who are looking for a full featured integrated, with phono and headphone stages coupled with balance and tone controls, I cannot think of a better value today. I think that I can easily live with this integrated amp for years to come and resist my OCD tendencies to keep buying new gear.
Having owned a Luxman L-590AX, Accuphase E-470 and Gato AMP-150, I can say without reservation that the Esoteric F-05 betters any of these by quite a bit. Since this is a relatively new piece of equipment, I am not aware of any reviews yet. If you have a chance to audition this amp, please do - you will be very happy you did!