Howdy, fellow Pasadena resident.

The difference between IIDTool Pro (the $2k+ unit) and the "regular" IIDTool BT ($500 or so) is that the former is not locked to a specific VIN, so it can be used - in theory by an independent mechanic, the customer the Pro was designed for - on any supported Land Rover vehicile model and model year without restrictions. The cheaper one you want as an owner (the $500 unit) does everything the Pro can do, but it will only work with your LR4 once you "lock it" to your specific VIN with Gap Diagnostic during the tool's registration process. That's really the only difference, plus updating the firmware of the Pro model costs money (again, because that tool is designed for LR independent garages as an alternative to other diagnostic systems that use the same software or firmware "subscription" model to keep up-to-date), while firmware updates on the regular IIDTool BT are always free - you pay for the updates when you buy the unit. Features-wise there is no difference. If you ever sell your LR4 and buy another Land Rover model that's supported by the tool, you can keep it and pay GAP a small fee to switch the license to the new vehicle's VIN.