Compared to tools like Autodesks' Flame (linux native) Adobe©®'s programs are amateur; GIMP and Inkscape even more so. When you can't provide an AI or PSD clients will simply turn elsewhere. Unfortunately, not learning these tools is a career killer. Balsimiq, Inkscape and GIMP are not currently the industry standard and Adobe©® skills remain a must-have in a Web Devs toolkit. Sure you can design directly in the browser, but sometimes having a rough mock-up will help save your most precious resource-- time. I work with a dual monitor setup, one running ubuntu the other OS X.