That "string" dead horse floggin again

I've only tried flat wound strings twice.  Once on a Hofner Bass and once on an acoustic.  Neither were my instruments.

They felt kinda cool and slippery, which, you know, was cool and all.  But overall, they didn't have anything that really grabbed me.  On an acoustic, I still like a nice set of PBs the most.

Some people swear by them tho.  Different strokes and all that rot. 

Garland,

If the GHS strings have had little use, and if they will fit the Gretsch, I'd fit them to the Gretsch.

If the 12g Rotosound are a bit on the heavy side for you, try tuning them down a full step (two half steps), that's what I would do, get some use out of them, tuning down a full step may sound strange, but give it half an hour play time, it's quite a common tuning, and will feel like you are playing 11g strings.

The spare e string may come in handy, worth saving.

Garland,  I barely remember the sound of the ones on the acoustic guitar I tried, but I do remember what the bass versions were like quite well, the acoustic was probably similar.

I would agree with those who call them more mellow.  I actually felt they were more smooth sounding and mellow; the two different qualities being fairly distinct to my ears.

That is probably good in a whole bunch of situations and to a whole bunch of ears, but again, they didn't grab me cuz I like my bass (and acoustic) sounding a little more bold.   Also, it's not something I ever even thought about until I tried those strings but they made me realize that I don't necessarily like them  feeling  so smooth like that.  I like the textured feel of round wound strings.  It's something I had to get used to and didn't love (but didn't hate either) when I used to use Elixer Polyweb strings, which, are not available anymore in my area.

If I had to call a set of strings "dramatic", I think I would go with this one set of strings I tried once that I just don't see even available anymore.  They were DR Dragonskin PBs.  They were louder, had a cool tone, and had this bold, almost piano-like sound to them.  Now those suckers were dramatic to my ears. 

Garland,

I think most Acoustic guitar players have at sometime or other tried Electric guitar strings on there Acoustic guitars at least once, and most ended up saying once was to many, including myself.