I'm in the process of deciding which of 2 ukuleles to make reentrant, & will keep the other linear. While it's obviously something that is personal preference, it made me wonder if people tend to have a sound (brighter vs. more mellow, for example), or woods (koa vs, mahogany, for example) that they prefer for low g or high g.
For me, it depends on the sound profile of the specific instrument, as well as scale length.
Typically anything shorter than a tenor, for an unwound low-G the string will be too floppy and will sound 'tubby' as well as have very little volume in comparison to the other three strings, whether a 0.0358" or 0.0410" fluoro string or a 0.0444" nylon string, yes all UNWOUND.(all easily available as classical singles from Strings By mail)
The aforementioned characteristics also are more closely related to not having enough string tension on a scale length shorter than tenor.
Thus, WOUND strings are often used for a low-G on concert and soprano more often than UNwound strings.
Some wound strings in use for tenor might be an 0.030" and for concert an 0.033" and for soprano an 0.035" (all from standard classical guitar string
single strings, easily available from 'Strings By Mail' or 'Strings And Beyond'), each of which will yield approx. 11-12 lbs of string tension on the respective scale lengths mentioned for each string diameter here.
I'm not going to re-open Pandora's Box for whether or not smaller bodies can effectively resonate a G3 note, nor am I going to debate the pros and cons of wound vs. unwound low-G, as both topics have been beaten to death here on UU in the past.
You can search and find those threads.
If you are deciding which of 2 different ukes to make re-entrant, that is a highly subjective personal choice. My best advice is to try them
both, side-by-side tuned/strung that way and see which you like best. Whichever you decide is the correct answer. Nobody else can tell you your own preferences, that is something only you can answer.
It is a personal choice for each player. Experimentation is necessary to find the answer, there is simply no other way IMHO.