Thanks all for the welcome, looks like a lot of knowledge here. I did listen to scanners some 8 or 10 years back with a table top Uniden 800 mhz and also had a handheld. It got to the point you could not pick up all the conversations when the trunking started so I kind of got out of it. The BCD996P2 looks good, I have never used a Whisler brand but I know they are good units. I really don't anticipate traveling with my scanner reason I'm looking at tabletop models. Can all these units be upgraded via computer connection?
ALL of the scanners mentioned can be programmed with a PC.
For the 436HP/536HP from Uniden, you can handle programming with the Sentinel software that Uniden supplies (free). There are also third party software programs that work as well, but you can do all your programming with Sentinel. I would also mention that the HP-2, also from Uniden, is programmed with a different version of Sentinel. Note that while the HP-2 can handle what the database shows for your state, it cannot be updated for DMR (needed if you also wish to monitor Ponotoc County).
For the Whistler units I mentioned, EZ-Scan software from Whistler, which comes with the scanners, handles your programming.
For the Uniden BCD996P2 (the handheld version is the BCD325P2), you can use FreeSCAN for much of your programming. However, as ofd8001 noted, these two do not handle large systems quite as well as the 436/536 models. Also, programming them would have a higher learning curve than the database scanners (Uniden or Whistler). If you decide to go with the 996P2 (or 325P2), you would find it much easier if you also became a Premium Subscriber to RadioReference, at least for the first 3 or 6 months, so that you can import programming data via software. (Subscription is NOT needed for the database scanners.) Also, the 996P2 and 325P2 can also be upgraded for DMR. However, if you need to program DMR systems, you'd need to purchase either ARC-XT or ProScan software, as FreeSCAN was not updated to support DMR systems. I prefer ProScan, because it also supports multiple other Uniden scanners, including some of my older ones. However, both programs have a 30 day free trial period, so that you can see which one you like better before purchasing.
I understand your thinking that you are leaning toward a base/mobile model for tabletop usage at home, and you don't plan to travel with your scanner. The base/mobile units usually have better audio (because of a larger speaker, inside of a much larger case), and their metal housings help minimize interference from other nearby electronics (a pc, broadband modem, printers, etc). However, a hand-held model, along with an ac adapter, can also be used on a tabletop. Besides that fact that, with batteries, it can be carried from room to room if you so desire, the batteries also keep it working even with a power failure, such as that caused by severe storms.