The Model I bought is the Segger Jtag-EDU for educational purpose: http://www.segger.com/j-link-edu.html
The price should be arround 50Euro.
It will give you a profesional supported product that should be usefull for many years. There are many ARM based uControllers out there these days.
The offer includes free use of Unlimited Flash Breakpoints. The only limitation is that it may not be used to develop a product.
The J-Link EDU is natively supported by IAR EWARM, KEIL µVision, Rowley Crossworks, and CodeSourcery G++. Via GDB-Server, the supported tool-chains also include Atollic TrueStudio, Yagarto, and other GDB based or compatible development environments.
J-Link EDU is sold to private persons, colleges, schools, universities and NPOs (Non Profit Organizations) for educational purposes only. It is not sold to companies.
I bought it from Farnell, but Digikey, mouser also have them.
I works fine in Atmel Studio 6 after an update of the J-Link firmware.
I use if for jtag based Programming and Debugging. I have not tried SWD and SWO yet.