I just got a Scrollpoint Pro from a seller on Amazon. It's a very comfortable mouse. It's very similar in shape to the Logitech G700, but with a slightly higher curve on the left. This leads to a hand position that's rotated at a slightly higher angle.
The Scrollpoint Pro's sensor is located in the middle of the mouse. I tend to use a claw-type grip with middle-sensor mice, but this mouse is too high for me to use a comfortable claw grip. I realize now Logitech's wisdom putting the sensor toward the front of the G700. On the G700, you can move horizontally with a "yaw" motion - you can keep the back of the mouse anchored and rotate the front of the mouse several inches side to side. On the Scrollpoint (and other mice that have the sensor in the middle or rear), you have to move the whole mouse for large horizontal distances.
The ScrollPoint Pro's 800 dpi is fine for multiple monitors at high sensitivity (I usually run a 1900x1200 next to a 1600x1200 in portrait mode. My sensitivity on Win7 is set at 9/11, with no acceleration. Forget about gaming with this thing if you use the wheel for anything--the Scrollpoint is useless for switching weapons and has no tactile tilt function. The sensor is a standard 800 dpi optical sensor, the same as on the original Scrollpoint and countless other mice. It seems reliable.
The Scrollpoint Pro's side button is a vast improvement over the middle button on the original Scrollpoint, but the tilt buttons are mapped to the Scrollpoint to retain Intellimouse compatibility. So that leaves only three buttons: primary, secondary, and side. They have a nice tactile click but are not too difficult to press. They can be remapped with the Lenovo Mouse Suite, but sadly not to any modifiers. It's nice to have a CTRL button on the mouse for zooming or an ALT for Photoshop.
Happily, the IBM logo is placed such that it's not in danger of rubbing off.
The Scrollpoint joystick itself is different from the one on the original Scrollpoint mouse. It's the same width but thinner front to back. The texture also seems rougher, giving a better grip. The new design is a little easier to use.
The IBM ASM P/N is 24P0504, and the FRU P/N is 24P0505. Most of the 800dpi Scrollpoint Pro Optical mice had the P/N 31P8700. I don't think there's any difference.
It looks like this place has two in stock for $45 each. I don't see the Scrollpoint Pro becoming my primary mouse, especially since I love my G700 and have gotten used to having 13 buttons at my disposal (as I noted above). But the Scrollpoint Pro will have a place on my desk for reading long documents and navigating spreadsheets. It's a much better design than the original Scrollpoint mouse. Interestingly, the Pro is even comfortable in my left had. It's not exactly ergonomic, but hardly worse than the original MS Mouse/Intellimouse.