8 Krypton

RE: pen compatible with touchscreen xps 15 (9550)

This system uses a touchscreen - not a digitizer panel, so it's not designed for full-feature tablet use like the 12" XPS is -- any stylus you buy will work exactly as your finger does.  It's not a pressure-sensitive write-on screen - if you need that feature, there aren't many 15" systems that offer it.  That said, you can use a generic stylus pen like


(just for example;  others will work as well).