An electronic HSI is no advance.  A moving map replaces an HSI, that's progress.  If you want to know your "horizontal situation", try an MX20 with the holding pattern displayed in magenta!  That was a chore, even with an HSI.

Mike,

 

Verrrry Interrrrrresting!

 

I completely agree about any HSI if one has a GPS.  However, moving map aside, I find the two most useful horizontal reference numbers are bearing and track, both digital.  I must admit that when I first started flying charted holds with the G430, I still did timing - no more since the racetrack expands or contracts relative to your ground speed - I just stay within the lines.

 

I do appreciate the DG or vertical card compass to occasionally help re-orient my brain (master reset) as to exactly where that digital direction is relative to where I am pointed.

 

 

Hmmm, I use the digital airspeed displayed on RMI micro-encoder more than the backup needled airspeed indicator.

 

My EPI 800 displays have incremental bands around each that I never look at as the digital representation, after some experience, was easier to interpret.  BTW, I do utilize idiot lights for out-of-bounds engine parameters and voice/sound alarms for edge-of-envelope lapses.

 

 

I love all digits, all ten of them and all the combinations that one or more might be configured.