Not exactly plug and play... I'm using it for mapping, and for some odd reason Emlid doesn't recommend using their GNSS as the primary system for navigation with Pixhawk.
So I have the Reach (the original and the M2- but the M+ would be the same) tucked into the area under the Solo GPS. There is some screwing around to get power to the Reach, either through soldering on the mainboard, or tapping into the accessory bay.
Mounting the Reach antenna is also a pain. My systems are pretty quick and dirty, per the pictures. Using the original Reach antenna velcro-ed to the top of the battery was great, but having a secondary mount for the CP antenna is less elegant.
For mapping, using primarily a Sony Nex5t, and then PPK with the Reach. Modified a mount from Ian.
Newer system will be using a 24mp mapping camera from ADTI. Worked with Ian to make a custom mount for this also. Haven't really used it for mapping yet, but should be superior to the older Sony.