I have the Vertex VXA-220 Pro VI
I like all the scanning features and it's portable. I sometime use it on one of my ATC feeds. I know Caleb may disagree on this one but I found it to receive just as well as my BC15X. They have pretty much the same sensitivity. The Vertex does have good selectivity and better adjacent channel selectivity and is not easily overloaded like the BC15X. I think we all agree that the squelch is a little pain to adjust but I can adjust it very quickly now and you can really crank up the volume and make it VERY LOUD. I bought it hoping that I could hear some weaker signals more clearly but that didn't change; to me, at home hooked up to my antenna system, they both sound the same. If you haven't already, download the manual and get a feel for this radio before making a decision.
KEL
Agreed for most part
Squelch is pretty well for being digital, and really doesn't take that big of steps. I keep my radio just right above noise (level 2) it does have a side button where you can break the squelch (hold for two seconds for squelch to stay off)
I found it better than my Radio Shack PRO-163, and with the same antenna. It is better at pulling in those long distance signals. Not by much, but sometimes it is what makes it from being there just above the noise to not hearing it at all.
As Kel said, it is an extremely hard radio to overload- radios that I had to use a FM trap on I didn't have to on the VXA-220. I think overloading is one part that makes this radio better than my Pro-163. Some extremely weak signals wouldn't be audible on the Pro 163, but would be just over noise level on the VXA-220. I think it's the rejection is that reason though, and in microvolts, it is more sensitive. It probably is a little less of competitor at the BCT-15X level, but these RS 163's overload.
Also, has a very great battery life, (at least 6 hours on RX), built like a tank, great customer service, and has its own charging case that is mounted on the desk, so it is like a base radio almost! It's five watts does the job, too. The stock rubber ducky antenna is a very great antenna for being portable, and matches the radio perfectly so that it is submergeable.
Caleb