Considering either product for my full frame A850, the Sony magnifier seems to be more of a when you need it, clip it on product at 2.3x and the Tenpa 1.3x seems to be more of a permanent accessory add on.

Just curious what people's experience has been.

I'm using the M focus screen and I use almost all manual lenses. Occasionally I find that sometimes my infinity focus isn't super precise so I would like to have more magnification to verify when I'm focusing to infinity.

I do not wear glasses or contacts.

I have no problems with close or medium distance shooting.