Hi, I have a top 27" iMac with SSD Lacie thunderbolt that I use as boot drive. It is worthed to spend more money and buy the new IMAC with internal SSD or I should just go for the Mechanical, and reuse my Lacie SSD? I guess the second, since the performance should be similir, so I will save lot of money. Is the top gamma CPU the same of the previous IMAC? Thank you.