The Afedri appears to be a pretty good value, as it is quite a lot cheaper than many of the other popular options - at the expense bit of performance.
Keep in mind the AFEDRI is one of the SDRs that I do NOT have hands on. I have not compared it against the SDRs I have and use, or have had and used first hand, such as the WinRadio G31DDC, G33DDC, RFSpace NetSDR, SDR-IQ, and SDR-14, Microtelicom Perseus, SoftRocks of several flavors, Soft66LC, QS1R, etc.
But, looking at the specs and talking with people who have or have used the AFEDRI I think the performance shortcomings come down to 3 issues that many people will be interested in. Raw sensitivity, dynamic range, and imaging. And as far as I know those shortcomings have not been quantified, only identified as issues.
Raw sensitivity is the one that gets most peoples attention, but to tell the truth it is not all that important. The sensitivity looks to be slightly better than the SDR-IQs is, and slightly worse than the Perseus. If this is the case it is significantly worse than the G31DDC or the G33DDC. If you have the advantage of living in a quiet location (form an RFI / noise standpoint) this might be noticeable. The average city dwelling listener will probably never tell the difference.
Dynamic range and imaging are going to show up in dense and crowded RF locations. If you have BCB transmitters near or other strong sources of RF this might be a real image. A suburbs or country dweller might not have a problem but I bet it would show up for a city dweller.
However, I have to say, if I was looking to get into an SDR to see if I liked the technology or as a first SW radio I would have to put the AFEDRI very high on the list, if not at the top. If I was a long time SWL, used to good equipment and looking to get into the SDR arena I would have to look at one of the better, but more expensive, offerings on the market.
And to the original question, I have no input on MAC stuff, have not used one in years.
T!