I’m scheduled to take delivery of SR22 #176 at the end of March. I must choose one of the MFDs. From various posts on this site, can I summarize the trade offs as follows (plse let me know if I am missing anything important)?:
ARNAV pros: engine monitoring currently available; FAA contract for free weather uplink; $3,950 cheaper
ARNAV cons: cannot display heading up (only North or ground track up); cannot display traffic without forcing clear of 430 info
AVIDYNE pros: better resolution of display; can display heading up (which better matches Sandel HSI format); can integrate traffic with 430 output; ORBCOMM weather uplink (is this a plus vs ARNAV system?); Cirrus choice for the future
AVIDYNE cons: no engine monitoring (so far, anyway); more expensive; not yet proven in the field

In my opinion the only significant improvement with Avidyne would be approach plates and enroute charts. This is or will be an option with Avidyne using Jeppeson Flight Max? or some such name. It will require a CD reader in the Avidyne. If the one Cirrus provides is already equipped this way then I would certainly op for it, however if it is not I would go with the cheapest alternative (Arnav) and wait for the unit which will do plates and charts.

A few additional comments:

1.) ARNAV gives you North, TRK, and desired TRK up.
2.) ARNAV does have all of the victor airways available so I am not sure what else you might be referring to with regard to enroute.

I made this same decision back in November. I am much more comfortable with my decision moving forward, especially since ARNAV has a significant upgrade that will be available in April. This will bring the Skywatch display to the ARNAV. It will also offer a significant improvement in resolution. The only thing that I really miss is the availability to have an approach plate displayed on the ARNAV, but in reality, I never saw a commercial pilot who did not carry a case full of charts and plates…so even with the display, I suspect that you would still need to have paper along anyway.

I think that Cirrus was smart in offering the Avidyne display. Other than engine monitoring, it really is a nice display. More importantly, it seems to have spurred ARNAV forward in their product development cycle. At the end of the day, I would suggest that either will work well (assuming that Avidyne offers engine monitoring quickly). So now the issue comes down to cost.


If the enroute question is in reference to my post, then I mean real IFR enroute charts with MEAs, MOCAs, MRAs, and the rest of the stuff you are supposed to have available to fly IFR. I believe the Jeppeson system also provides sectionals for the VFR types.