Is anyone using an AT 150MLX (or another cart that specifies 100-200pf of loading capacitance) with their Nighthawk?

I'm looking to pick up a new headphone amp to replace my X-Canv3. Currently driving a pair of Sennheiser HD650's. I'm considering the Mapletree. It uses 5751 input tubes and since I have a bunch of that type on hand, it seems like a practical choice. How does the Mapletree compare to other...