Full Wave Rectifier

Hey man, sorry for taking so long to respond. To finally answer your question as to why I've implemented the precision FWR fhe way I did (http://everycircuit.com/circuit/5833877661941760) is because of output loading. Your circuit works fine as a FWR, but as soon as you add a load to your output you will observe very undesirable behavior at the FWR output. Where as with the precision FWR the output remains the same, regardless of the load. For your circuit you will see that a purely resistive load will cause an asymmetric amplitude response between halfcycles, and a reactive load completely alters the output. But I see you have made a reference to impedance matching at the output. This can be very tedious and isn't very flexible (ie the matching network might have to change if the load is changed).

Hope that answers your question?

The simplest way to overcome the issue of loading would be to simply buffer the output using a second opamp, but that is essentially what the precision FWR does. Also notice the increased total harmonic distortion at the output of your circuit, which won't be solved by simply adding a buffer