In my opinion the Wilko 30 bottle kits seem to contain flavourings. If I'm right, making one up to 6 bottles would result in a very strong 'flavour'. It may be ok - or not. My wife made the Pinot Grigio (to 30 bottles) and it is not unpleasant. I seldom drink white wine so difficult to say more. The reds are nothing like a decent wine in so many ways. I haven't done a 6 bottle kit, they may be very different.
I'm pretty sure I read a review of the pinot grigio in the wine kit section and the comments were quite favourable.