If you choose to go with a Unication G4 or G5, be aware that it is a pager, not a scanner, and it has limitations. You can only scan one system at a time. You can only scan so many talkgroups at a time (16? 20?). You cannot hold on a talkgroup, it is constantly scanning. And you cannot lockout or avoid a talkgroup that you don't want to hear at the moment.
If you decide to choose to have a commercial grade radio programmed for non-affiliate scanning, there may be options other than Big M that are easier to get programmed for non-affiliate scanning, which reduces the chances of the radio being detected on the system and "bricked" remotely by a system administrator. There are also limitations with commercial radios compared to scanners. You may be limited to scanning one system at a time, and you may be limited to scanning only a limited number of talkgroups at a time. (The radios used by RWC agency's have 16 channels per deck. If you have it programmed to scan, you're limited to 15 channels, with the scan mode in the channel 16 slot.)
I believe it was you who asked the same question on the Yahoo group. If you haven't yet, look at my response over there.
John
Peoria