The Eye-One calibration software is PPC only, they have not shipped a single update in the three or four years since I bought the hardware.I have already offered a solution to your dilemma and that is to partition your HDD. No requirement to new anything.
And even though it will likely work to do a display calibration under SL and then copy the created profile to Lion, I would not want to guarantee that this will work. The profile contains LUTs, to be uploaded to the graphic card, there are things that can go wrong when copying such low-level configuration files from OS to OS.