You are assuming that the site is in range and an active control channel can be located each scan. I literally saved seconds (seconds, not milliseconds) on each scan deleting voice channels particularly from the Fort Worth System for which I am usually just on the fringe of several sites. Two of the sites are hit or miss whether I get a control channel on each scan. Four sites I only get a control channel when I am mobile. Made a huge a difference in my case.
Same results here, however I program locked out duplicate sites with all frequencies in case I need it mobile. I also found that using a combination of site hold, quick keys, and lock outs make a HUGE difference on getting the radio configured to how you want it in a rapid manner. The same radio can be fast or slow depending on programming...
Overall: If you even think about monitoring a simulcast digital trunked system, SDS### is the way to go. If you have more conventional things in mind, digital or not, BCD#36HP is a good idea but the prices are close enough that I would have to think about it. Nothing beats this ancient BCT15 in pure analog conventional though. It's like anything else, with choices come with some give and take. Go with what's best for what you are listening to "most" of the time.