Not stable at 2. 5Gb
"Asking this adapter to negotiate between the 10Gb SFP+ and a 2. 5Gb downstream device is not workable. It seizes up on the downstream side after it heats up. Tried it with two of them, and both exhibited this behavior installed in a Ubiquiti switch. Went back to Altex and got an Intellinet 5 port 2. 5g switch with SFP+ port and an SFP+ crossover cable, and that works like a champ. Lesson learned. I have no doubt this would work at 10Gb on the ethernet, but I would not use it for anything slower."