They're all similar with different pros and cons.
(Con)Subscribestar takes 2 weeks to process payments, (Pro)Patreon and Pixiv gives you the money faster.
(Con)Patreon allows NSFW but wants to be family friendly cause Paypal is breathing down their neck. (Neutral)Pixiv allows NSFW so long as its marked as sensitive. (Pro)Subscribestar doesn't give a fuck.
(Con)Patreon deducts 16%(+3% Paypal processing fee) from what you earn, (Con)Subscribestar deducts slightly more than Patreon but deposits it directly into your bank account which could be a pro or a huge con, (Pro) Pixiv Fanbox doesn't deduct anything but your fans might end up paying JP sales tax(15%) and their own countries tax(5-25%) and Pixiv sends it to Paypal so the only fee is 3% for processing.
(Con) Patreon and Subscribestar require paperwork and takes a few days to complete registration. (Pro) Pixiv Fanbox doesn't require any paperwork whatsoever and deposits the money to any Paypal account you want(Pro but also a huge security risk if you leave money on your Pixiv and it gets hacked)
(Pro)Patreon and Pixiv Fanbox take recurring monthly payments/subscriptions from fans. (Con)Subscribestar says they don't do this but I'd need to confirm.
(Pro) Pixiv Fanbox is marketed toward fan loyalty while (Con) Patreon and Subscribestar treat artists like a business that are supposed to produce paywalled content.
Ko-Fi is only for one time donations that are made on a whim. You can have a Ko-Fi open if you feel like getting spare pocket change, but don't use it as your main thing.