Tama CB90R Iron Cobra Rubber Beater

I'm sorry to say this, but this product is just bad. I am a Tama fan, my drumkit is Tama, but these beaters are not up to their usual standards. After playing only a few times with them, both beaters (I use a double pedal) started to have the same problem : no matter how hard I tighten the bolt at the back of the head, the beater head starts to slowly tilt while I play - up to the point where it's actually hitting the drum head with the side of the head !!! ). I bought this exact type of beater, but with felt heads about 10 years ago, and played the crap out of them. Never with problems. I guess quality nowadays just isn't what it used to be