These have a Silicon connector seal so don't have a rubber smell but vape terrible anyway because the coil doesn't have non/res/non wire so it burns the silicon seal. But when properly rebuild using non/res/non wire these are great. Is it worth the hassle? For me it is because you just can't buy replacements heads (even genuine ones) that don't smell like a rubber.
These BCC still come close to carto tank when it comes to flavor no matter what.