I dont care how rare it is to get, its an absolute gut punch to throw away 5500 training. Unless theyre gonna put in (equally rare fine) a bundle or something, toppers and all. Its not remotely balanced.
Related note, why does anyone ever do sets? Lol i never do but did in order to get some zero chill xp to get season xp bc it was the last way available (not doing online event because im not buying the obscure players for lineup requirements) as usual, literally lost coins doing the set.