And fees for Gemini look a bit off (unless it's showing Polish fees and not US fees, in which case I am probably wrong).
Evilish, had a quick look at Gemini fee schedule and how we calculate them and it looks fine at first glance, do you mind elaborating a bit on the "offness" of their quote? If you prefer, feel free to DM me here or on twitter (@bitcoinpartypl).
Cheers!