Installation and Migration:
Went really simple: SSD built in a If ordered, external case with Carbon Copy Cloner (30 day trial) within 6 hours approx 450GB copied. Then just the old hard drive out and the pure SSD (you need Minikreuzschkitz and Torx, the Hama Mini Screwdriver Set have in case). Could boot directly.
The first boot process takes any longer because the hard drive is no longer stored as a boot volume and the system has to look first. For this search in Spotlight "Startup Disk" and then select the disk as such.
Power:
Outstanding, everything starts in seconds. Especially Parallels starts, runs fast and smooth. Because the system uses the hard drive as memory when RAM is fully occupied, it will work with many open, memory-hungry programs with an SSD still fast. It is also absolutely silent.
Conclusion:
Absolutely satisfied, unless otherwise breaks on my Macbook, I think my performance a few years will be sufficient. Too bad that the new MacBooks are no longer so easy to upgrade. Have been with my simple and inexpensive addition to the hard disk
the battery and the memory exchanged / upgraded, that no longer works with the new, unfortunately. Next on the program is to upgrade the internal CD drive to another SSD. :-)