Hi! I have a iMac 27 "Late 2012 with USB 3.1 Gen 1 + Thunderbolt 1. I would like to buy an external SSD portable hard drive. I was thinking of the Transcend StoreJet 500 because it seems to me the only one with a Thunderbolt 1 port that reaches theoretically: Read: 440 MB / s Write: 300 MB / s Then there are an infinite number of other SSDs like the - Samsung T5 - Western Digital My Passport SSD - SanDisk Extreme SSD But I'm confusing myself with the real performance they achieve compared to the Transcend StoreJet 500 because they always mention USB 3.1 Gen 2 and therefore I can't understand connecting it to USB 3.1 Gen 1 what performance you get. I believe I should choose Transcend StoreJet 500 because Thunderbolt 1 is superior to USB 3.1 Gen 1, don't you think?