Had the Trinity system installed in my Guild F50 by a local luthier. Could not be happier with the sound. I am running the guitar stereo cable into a DTAR Solstice then out to a pair of powered QSC K10 PA speakers, this is my basic setup. I am able to not only effectively blend the mic and soundboard signals with the DTAR but also eq both signals independently to really dial in the desired tone. I have found that the best blend setting is about 30% mic and 70% soundboard with almost all the low eq rolled completly off and mid and hi eq's set at flat. Proper QSR speaker placement is a must to avoid any feedback from the Trinity mic, just experiment with speaker location at home to get a feel for what works best for you. I also have a Pure Minii system (without the mic) in my Guild J30 12 string and will be installing the Trinity mic upgrade soon. I have tried a dual source Sunrise magnetic pickup with a Fishman UST piezo for the past 10 years and I would say that the Trinity has a dramatically improved natural sound.
I've got K&K for a week and can't be more happier! Before that I had LR Baggs M80, it sounds great but it's somewhat bulky and changes the sound of the unplugged guitar so I had to remove every time I wanted to play unplugged - very annoying. K&K Trinity compared to M80 not only doesn't change the sound of my guitar, it sounds fantastic when plugged through an amp. Installation is pretty straightforward, I did it myself and that wasn't that hard. The microphone sound is a bit boomy and needs some minimal eq'ing. I haven't tried Trinity Pro Preamp yet, I ordered it separately and it's on its way now. But the sound I get now through an 2-input audio interface is really amazing! Thank you John.