I've seen some that really like it but I haven't seen a lot of talk about it
Currently, my favorite RDAs are the 454 BB, Veritas, Plume Veil, and the Magma. My 454 was cheaper than the others by some $45.00. I have had the 454 and the PV for about 4 days, now. Personally, I think that the 454 offers the best build quality and overall performance over the others mentioned.
I have not used the negative trapping ring the way it was intended. I have been tying down the negative lead between the screw and the said ring.
I like the flavor and vapor production on mine but I've always had an issue with the center post spinning and stretching the coils when I tighten the post screw. It seems the center post is press fit as I can't tighten down the positive contact to it.
No problems with the center post on mine. Have you called the vendor for an exchange?