I do - I've got an old Spyder2Express. Makes a massive difference, particularly on older monitors where the backlights have aged.
That said, I would strongly not recommend a Colorvision/Spyder one. Their treatment of Linux and FOSS stuff is horrific, and despite you buying the hardware, you still have to keep the software key.
Yea but its not that bad to keep the software key but they work good for windows? so do you think it is worth it for new ips monitors to get the best colours? and new hd tv's ? or my normal 1080p led monitor?
So for that you think that the calibration makes a big difference? i think it would be good for the single reason of multi monitor setup so you can have them all show the exact same colours