I'm afraid it was 2+ years ago so I don't remember, but it must have been slower than the comparable speed from the gigabit wired connection. FWIW, I was so happy with the Sonnet (not as hot as some alternatives I've used) that I bought two more. However, unless you are using fiber or for other reasons preferring SFP+, going with the grain and getting 10Gbase-T is probably easier.
Getting back to the OP, this could be interesting for me if and only if I can get fiber based Thunderbolt-4, but it seems to not yet be available.
Thanks. $528 for 30 meter TB3 compared to $35 for 30 meter OM4 and a pair of $10 10G SFP+ modules (and the same OM4 will carry 25GbE just fine). Seems like it's not really cost effective.
Can you quantify that? (I'm wondering if it might be good-enough for my needs.)