I would say the difference wasn't so much flavor as it was drinkability. The flex tank version was smoother, tannins were settled, and overall more enjoyable.
Ok, so I have noticed something that I thought I'd share with you all. I have a FWK Cab Sauv / Merlot blend that I bottled a month ago after aging it 14 months in my Flextank. The same was aged in a glass carboy as well. Wow, no comparison imo! The Flextank allowing for micro oxidization...
Personally, I wouldn't pick any of the three options. I don't care for these lower ends kits and would opt for a FWK Riesling or En Primeur White Trio instead. But, if these were the only options....Riesling as CRU is a higher quality kit IMO
Well perhaps it worth looking at stepping up to frozen must?
$109 delivered
https://www.grapemust.com/product/merlot-grapes-livermore-california-2020-frozen-must-6-gallon-pail-bucket/
@winemaker81, I am not so sure about that..,I know from chatting with Matteo that they use grape blends in there. Perhaps some fruit and "fruit flavoring" or concentrate as well. Point being that they are for sure not 100% fruit concentrate.