I disagree with Stefan, but it may be a matter of personal taste. I started with a Graphire (Wacom's predecesor to the Bamboo line) before moving up to the medium Intuos. I thought the difference in feel was huge, and I wouldn't go back.
Besides the size, the Intuos line has some other benefits over the Bamboo line, including pen angle, greater pressure sensitivity, and programmable buttons and dial. Pen angle won't matter much unless you're doing fine art, but the additional pressure sensitivity is nice in Photoshop. Programmable buttons is big plus for tablet-as-mouse-replacement, and you can set up the buttons (with little OLED panels) on a per-app basis.
If you're on the go a lot, consider the Intuos Wireless. I have a couple of those here. They're about the same size as the medium, and they can connect via USB, but they can also unplug and connect via Bluetooth.
Using a tablet will take a little getting used to, but once you get the hang of it, it's hard to go back to a regular mouse. I use my Wacom in conjunction with a trackball, and I no longer keep a regular mouse on my desk at all.
Walter Soyka
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