Cheap Ebay roller rockers. Too good to be true?

Never bought or experienced them. I will say, I've known some that have taken the step and couldn't use them due to bad quality
I have had hit and miss experience with cheap Chinese knockoffs. Iv had some stuff be ok and work fine. But on the other hand I bought 3 different sets of Chinese ripoff broadheads they where rage knockoffs swakers and muzzys. They where cheap cheap. Like a couple bucks vs 40 or 50 for the name brand. And they looked just like the real thing until it came to shooting them the rages just came apart. They flew great but the animal they hit completely destroyed them. The swakers wouldnt fly. They flew like a bent arrow would fly. The muzzy knockoffs where not bad they where just dull. I have never bought any chinese car parts tho.