I finally decided to upgrade my one year old MacBook Pro. I replaced SuperDrive for anothe disk. I ordered OptiBay from USA. For 200€ (99$ unit, 70$ shipping, 60€ customs) they send you an adapter for the disk that you put inside the Mac in place of SuperDrive which you can put in a external USB enclosure.
Replacing the unit wasn’t difficult. You follow instructions and where the failed you follow your common sense. I had some problems with puting the SuperDrive in an external enclosure, as there are no instructions for that, but not much.
I want a clean install so I have to install all the applications again. In the future I will replace the disk for a faster SSD, but their prices need to come down a bit.