Last year, something unique to Sol & Luna happened to us for our Valentine's Day dinner there. Our CC was charged 20% more than the amount of the check. When I discovered it while checking my CC transactions online, I emailed the owner who replied to me that it was his bank who was charging 20% more, not them, that it was temporary and that I should be credited of the difference in a few days. It sounded very strange to me that a bank would do that. I called my CC Company and indeed they refunded me of the difference without any difficulty. I wonder what would have happened if I didn't notice the discrepancy.
No other SXM restaurant ever charged me more than the amount of the signed CC receipt, not even temporarily so this was a very unpleasant discovery.
I will add that I left a small "pourboire" of $5 in cash on the table, knowing that service was included. Who knows if they didn't decide to "pad the bill" since my tip was small.