1 - 2 horas
wanted to avoid the insane Apple surcharge for an SSD Mac Mini, and also wanted to keep the original HDD.
Disassembly and installation of the SDD went straight forward with the iFixit Guide. Reassembly was a bit troublesome, some hints (including images) would've helped. After that I tried to install OSX 10.8.. to no avail. The Installer copied its files, but the didn't continue. In desperation I again opened the Mini and SWAPPED THE SDD and HDD positions, which also meant switching the SATA cables. Hoping, I put everything back together, and to my relief the Installer did what it should.
One little problem remains: Mountain Lion can't be downloaded from the App Store, because 'The Computer isn't compatible'. Strange! It's running smoothly right now!
I hope when OSX 10.9 comes, updating will be smooth and that recovery disk-business isn't necessary.
Also watch some of the videos regarding dis-/ reassembly on youtube.