Hi. I've got an old Ovation Celebrity that I converted to Nashville tuning about 5 years ago (I play mostly Country, by the way). I use it on my home recordings in 2 ways. Firstly, as a strummed rhythm guitar, set at the opposite end of the stereo spectrum to my 614ce,which has standard tuning. That gives an additional lift, or lightness, to the rhythm section and is great when properly mixed down. Secondly, I discovered that I really liked the effect of using it as an additional lead instrument, finger-picking, predominantly on the top 3 strings. The octave lift on the third string creates some nice sounds against the top two strings, which are the same as standard tuning.
I used the Ovation because it had seen better days, but it's still going strong. I plan to look into using my GS Mini, once the Ovation gives up the ghost (it was stated by the Taylor guy, at the last road show I attended, to be a good use of the guitar). I need to check the effect on intonation before that happens - there must be a lot of different stresses on the neck if you change from the very heavy strings recommended for the GS Mini to very light Nashville tuning strings. BTW, if anyone is interested in trying it, D'addario do a high-strung Nashville string set (.010 - .027) ref EJ38H. Hope you found the above interesting.