Here's the deal, In MY area, on the Day I tested it, on the System I checked it on, I could not tell any difference between the SDS 100 and a BCD536. Again that was that one time for about an hour (or so) on a simulcast system I monitor day in and day out. People will tell you or argue with you that they cannot do Simulcast. People that know the truth will tell you it may not, but it depends on your location to the towers in your area. If you have one tower close and the others are "some distance off", obviously that has a better chance of working than if you're right in the middle of all the simulcast towers. To be sure, if you're wanting to listen to simulcast, you should likely go with the SDS series unless you care about things like I don't know VHF analog or such nonsense. That's where the SDS stuff lacks. Of course you already have a good analog scanner so you could do what I do and use one device for the simulcast and the other for the analog duties.
IF you understand the limitations of a Unication voice pager that's the better choice for heavy simulcast. But again, it has limitations compared to a normal scanner. I'm told the SDS uses the same software the 536 does (and it says so when I open it up also) so it's not too daunting at all to program of you put a little effort in it. Everything is a learning curve. If I'm not mistaken the uniden DMR upgrade is $75.