Before buying two second hand Kenwood TM-D700 rigs, I owned its replacement, the TM-D710. I was planning on buying another TM-D710 when I found a pair of D700s for sale and figured that two rigs were better than one.
The D700 is still a great rig for general APRS and dual band use. My main dislike is that power settings are not saved in memory, but I think that is normal for Kenwood radios.
The APRS functions are a little hard to use, because you must hold the function key for 2 or 3 seconds to change the buttons to do their APRS functions, so, for example, to send an extra beacon, you have to hold function for 2 - 3 seconds, then press bcon, then hold function for 2 - 3 seconds, then press bcon again.
Don't let anything in this review stop you from buying a second hand Kenwood TM-D700 for a reasonable price. It is still one of the better ways to get onto APRS, and on the used market, considerably less expensive than the TM-D710.