In the context of a trail run, the digital mode is better than APRS. The touch screen and software keyboard are awesome! Even without the digital modes, this radio has some advantages in APRS over the FTM-350AR. This may change when the APRS manual is available. This radio has fewer screens than the FTM-350AR, so you don't see all the information that the FTM-350AR displayed. Fortunately, this this is pretty easy with the touch screen. RT Systems has not released software for this radio yet, so you have to program it from the touch screen. This will make it easier to send APRS messages. Voices sound a little different than analog FM, but you get the distance between you and the other station on every transmission. The radio is a little picky about which Micro SD card you use. I have not figured out the Group Monitor functions yet. I was also able to setup all the essential APRS functions. The good news for Yaesu fans is that I was able to get on the air without even opening the user manual.
These manuals are not on their website as of 9/21/13. The manual says to download the APRS and Group Monitor manuals from their website.
Yaesu supplies a manual for the radio in the box, but this manual does not cover APRS or the Group Monitor functions. It is a bit early for a full review, but I have noticed a few differences. I installed my FTM-400DR in the Jeep today.