When I was shopping for a pre amp I considered each of these mentioned thus far and ended up with the Mapletree. I never heard the others to compare. But I am thrilled to own the Mapletree. Simple circuit, point-to-point wiring, takes less expensive 12SN7 tubes instead of pricey 6SN7 (although can do either), custom gain for each input, separate power supply, wonderful personal customer support, separate channel gains ... all for under $1k new! Since I've not heard the others I cannot compare the sound, but can say that mine sounds wonderful and has worked well as a pre to ss as well as tube amps. Rolling tubes changes the sound to your liking. If the others are as susceptible to tube rolling as the Mapletree then I'd suspect any of these would sound great. Just pick one based on their features, support, and price.