I had my original call of WB6WKB for 24 years. When I upgraded to where I could pick out a new, shorter one I jumped at the chance. Saying 10 syllables (8 if Texan - grin - dub ya bee six dub ya kay bee) couldn't cut it before; now, "87 dB" does!
My final choice of AD7DB was not without serious consideration. I wanted one that was shorter to say, and not too ambiguous: d,b,c,z,e's all tend to sound alike, as do f & s, etc. However, when I checked to see what suffixes were available, I found my initials, and a good variety of prefixes. Then, there it was: AD7DB jumped right out of the list at me.
Now, why not a 6 instead of the 7? Because, someone else already has AD6DB, and, I don't plan on living in California forever, and expect I'll eventually be moving to some other western state such as Nevada or Arizona for the drier climate (health reasons). So, my call will fit right in then. Besides, 7 isn't far away from 6-land, nobody can really complain. (If I had a 1-land call in California I can understand some people getting annoyed that they didn't get a cross country contact.)
The suffix of "db" is still somewhat ambiguous on phone on occasion, but I don't have too much trouble with it. I generally use phonetics on HF anyway.
As I said, I had no hesitation about giving up nearly a quarter-century of WB6WKB for my new call. Some people have a harder choice because they're too well known for the old callsign. My brother really had to think carefully about changing his from WB6SAN. (I'd think that suffix would be particularly desirable for a California ham, with all those city names that start with SAN.)
Some people want a really short callsign to send on CW and don't care about what it'll sound like in voice modes; thus, E,T,I's are good. One tip I've heard from around is that a callsign with a dash instead of a dot at the end seems to work better in getting through pileups.
Anyway... consider your selections well and enjoy the custom callsign you get!
Dave AD7DB