2017 Swan still the best design. Pity I had no idea about bullion at the time. The 2021 is the next best imo. Bullion Now had a couple left (at around 5.5% premium, very well priced). And Apmex have some floating on their eBay store still too.
They have some deep meaning as far as "Black Swans" are concerned. I made a set of these with their silver sidekicks.