They are certainly very high quality. I have used one which is owned by a friend. The craftsmanship is just amazing. I think it's the only brand that actually fits a Ruger LCR.
If I have any negative thoughts about them, they are somewhat minor.
First, they do have a bit of rattle to them with rounds locked in. The design is for cartridges to be deliberately held just a bit loose to help with chamber alignment, so there is bound to be a bit of noise being metal to metal. Not a big deal but it's noticeable.
Also, they unlock with a counter-clockwise turn of the knob (to the left) which is opposite of the HKS knob release. Again, a fairly minor detail that unless you are old and set in your ways like me. It would be unnoticed by anyone who is using a speedloader for the first time or someone who wants to retrain from the HKS feel. I always turned it the wrong direction, which is only natural for somebody who has used HKS for 35 years.
How do you like yours?