I would give Mike @ Quicksilver a call, as he will be more than happy to give you an "impression" of what to expect with different tubes.
I ran my V4's with Ei KT-90 Type III's. Very linear, good bottom end control, liquid mids, not as warm as the KT-88's. Each amp was tested at 170 wpc configured with the KT-90's when it left QS production.
I ran my V4's with Ei KT-90 Type III's. Very linear, good bottom end control, liquid mids, not as warm as the KT-88's. Each amp was tested at 170 wpc configured with the KT-90's when it left QS production.