defbyteNot as similar as you might think: the KeySmart can be arbitrarily extended with extension posts and holds keys on both ends thus allowing for a slimmer profile. The BladeKey has that "shelf" the keys can rest on and prevents them from spinning full-circle, which might make for easier key flipping, in particular returning keys to rest position. This is mostly achieved by the KeySmart too though by having keys on both side stop each other inside it.