I have a ~2010 WD Blue 500GB laptop hard drive in my Linux desktop here. It takes about 15-20 seconds to boot to desktop. My Mac has a Kingston HyperX SSD (one of the ones people use for 4K+ cameras), and it takes about the same time. Boot speed has a lot more to do with OS and startup software load than the hard drive. Before buying an SSD, consider removing all your startup junk and clearing your desktop of files and shortcuts.