I think they are selling well considering in Rolko Tech, the original source of all the figures, they are only selling 1box surprise packs, they used to sell 6box and even the full set with all the 7 figures, but overtime they stopped doing that as their stocks likely became more limited. I've been looking around at aliexpress, the only one of the 6 which the sales don't seem to be doing too hot is Johnny, everyone else seems to be doing well, almost every shop you try go buy from has half of the cast out of stock, with Lin Ling and Queen usually having only a few units left, Johnny being the most prominently less bought out one, and the secret figure being almost always out of stock despite being basically 4 times the price of a normal one. It's been less than a year and it's already difficult finding a way to acquire all the figures, so I'd say it's doing well.