You might want to check out the weekend sale at XP-PEN (Click on 'Flash Sale"). I just purchased the Deco Pro M ($110 US shipped) to replace my Wacom tablet. The nice thing about these larger tablets (11x6 usable) beside being a great size for drawing, they are excellent for maneuvering over multiple screens (I use three screens simultaneously) using the pen instead of a mouse; more natural when you think about it I configured the pen to transverse the three screens when used on the tablet ('monitor' mode) and only one screen when used on the monitor ('Full Screen'), it is automatic once set up (a touch of a pen switch toggles to the other two screens). For two screens a smaller tablet might be sufficient.
The bonus with the XP-PEN non-battery pen tablet is that the tablet pen also works seamlessly with my XP-PEN 22R non-battery pen monitor. No need to go from a mouse or pen to another pen, same pen on both media!