It’s early, only been one day - but after hours dealing with remote interference issues with my used/new Gain Cell DAC i’ve pulled it out and reinstalled my Sprout100 as a pre-amp to a S300 amp. Is it bad that I actually prefer the sound of the Sprout/S300 matchup over the Gain Cell/S300 ? I dunno, like I said it’s still really early. Lots of listening still to do. 
Not bad at all; what works, works.