How is the functionality of the G5 compared to the SDS100? How does DMR work, I believe I seen its like $75 for SDS100
As belvdr stated, Unication units do not follow trunked DMR systems. For single frequency DMR monitoring you must know and specify the DMR talkgroup in addition to the frequency along with other parameters when programming Unications. For the SDS you just have to enter the frequency and specify either "Digital Only" or "All" under "audio type" and you are good to go. The SDS display will show you the talkgroup number, which is how I was able to program my Unication on the single frequency DMR used by a local school not yet listed in RadioReference.
As far as functionality, the Unication programming can at first be a bit intimidating, but once it is programmed you just turn it on and select the zone and knob position to select the talkgroups of the system you want to scan. This is great when you have a fairly narrow focus of what you want to hear. With just the turn the knob you can switch between 8 sets of talkgroups like "Local PD", Local PD and FD, " Regional PD", "Major Events" or however you want to organize you talkgroups for quick access. However, you cannot add talkgroups, frequencies or otherwise change the programming without using the programming software on a computer. And again, you can only monitor 1 site on 1 system at a time. Or, you can listen to conventional channels but you cannot scan a trunked system and conventional channels.
Programming the SDS via Sentinal software is easier than programming the Unication, but with many more options than previous scanners it is easier to make a mistake and find you cannot receive the system. For example, if you cannot scan a system you programmed it might be because location scanning is enabled or the service type is not enabled. The SDS scanners are much much more versatile than the Unications. You can scan multiple trunked systems and conventional systems at the same time on the SDS. DMR systems can be scanned.The SDS covers all public safety bands while the Unication covers only the two of your choice. Virtual control with logging on the SDS through Proscan lets you see talkgroup activity at a glance, easy to enable recording is helpful in determining activity on a talkgroup. And there are many other features on the SDS like Close call and display customization one might feel are helpful.
In short, I have found that both SDS100 and Unication G5 receive P25P2 systems very well. My suggestion would be that unless your monitoring of a P25P2 system is going to be very focused on limited talkgroups on that one system that your first P25P2 capable radio be the SDS100 or 200. With the SDS you can explore the entire system, find new talkgroups and check out DMR communications. Sensitivity may be less than other Unidens, but for 800mhz reception a dedicated 800mhz antenna on the SDS100 really makes a difference.
Good luck with whatever you decide to purchase!