I think you'll find the Legacy can climb direct to FL390 at typical weights, with FL410 soon after. Most flights here go straight to these levels, but things may be different in your part of the world. Still, the latest executive metal does operate much higher.
There is a program underway to study modernising the avionics fit, which is one of the less attractive aspects of the Legacy, using the Rockwell/Collins suite for the planned Legacy 450/500.
There is an option for LED lighting, which improves the cabin ambience a lot!
TTFN