I have tested a Retevis RT81 DMR UHF portable transceiver in order to debut into the DMR world.
Large, hevy, with a backward look, the RT81 worked quite well but appeared to transmit on both slots symultaneously. 2200 mAh battery, 12 cm long rubber single-band UHF antenna, it is characterized by a quite weak but usable RX audio output.
It is compatible with the Baofeng UV-5R speaker/microphones and programming cable. The programming software may be downloaded for free from the Retevis website and with some guidance from an expert user in DMR, it is easy to use. 32 digital channels and 32 analogue channels may be programmed. The antenna connector is the same of Baofeng UV-3R. After a while I dismissed it and now I am testing the Kydera DM-8500.
Here is the RT81 user manual: http://www.retevis.com/material/mannual/RT81-English-manua.pdf in pdf format.