Thanks pal, looks like a lot of people are favouring the older images, not had any problems with the built in wifi on the model 3?
Well, Here is why I expressed my earlier opinions. I had 8 RPi 3 boxes sitting on the bench ready for deployment and loaded with the March 2016 build of Jessie. These had been done a few months ago and set aside for future use. The job I needed to do called for 12 RPi units, so I ordered another dozen kits. When the kits came in I sat our tech at the bench with detailed instructions and had him perform dist-upgrade on the first 8 boxes that had been done previously. (Note: the tech bench uses a LAN cable to SSH into the units for configuration)
I also gave the tech instructions for installing the 2017-01-11 image on all of the new units. The first 4 of the new units were assigned to join the previous 8 units for the current job. The remaining new units would go on the shelf as hot spares or whatever next job comes up.
When we tried to deploy the units for the current job, all 8 of the units that went through the dist-upgrade failed to work with wlan0. Three of the other four units assigned to this job (the brand new ones with 2017-01-11 image) worked with wlan0 but were extremely unstable and would require reboot every few minutes to keep the wifi working. Only one of the new units seemed to work properly.
We took all of the units back to the bench for troubleshooting as well as the 8 new ones we had put on the shelf as hot spares. Of the 12 new units running the 2017-01-11 image, only 3 seemed to work on wifi. the remaining 9 units were unstable as described before. We also confirmed that all 8 of the units that went through the dist-upgrade would not work at all on wifi.
The first thing we did was re-image all of the original 8 units back to the March 2016, preformed the apt-get update, installed a database package that we use along with our custom database scripts, and tested again. All 8 worked again as before the dist-upgrade. Next we re-imaged all of the brand new RPi 3 boxes with the March 2016 image, apt-get update, and our programs and scripts. Voila!! All 12 new units now worked perfectly with wifi.
So, that was the reason for my comments about the possible image issues. However that does NOT explain why the 2017-01-11 image produced such unstable wifi on only 75% of the new units.
Regardless, we deployed the March 2016 image and shelved the extra 8 boxes with the same March 2016 image. At least we know those work. Since that weekend, I have also had the tech go back and re-image a few other boxes on jobs that are not wifi dependent back to the March 2016 image as well. Total of 40 units now re-imaged to March 2016. All future new purchases will probably be done the same way to save time.
Some day when we have time, we may try a new image again, but not sure when that might be possible. We use these in a non profit organization so there is not much incentive to do a lot of troubleshooting past "just getting something to work quickly".
Hope that helps.