not to burst your bubble - But I am going to have to say no on the Consistent levels in a bottle - due to the pump and all the factors that lead to this - I know you want a cheap bottle filler - but this is a trasfer pump that delivers over 3 gallons per minute.
VPM, you are probably right, but hey, it's the off season. If I wasn't tinkering with this, I would just be drinking wine. To get an idea on how accurate the fill needs to be, I took one on my clear Skeeter Pee bottles so
I could see through it. I marked it off and then using a 10ml pipette, measure the difference between the low and the high fill target. The difference was 6ml. So 750ml plus or minus 3ml. That looks like a pretty darn tight target.
I did anticipate needing to tightly control the stopping of the flow, so I also ordered a $5 12V water valve from eBay, that I could open and close with the same timer. I'm thinking that might provide a more accurate start/stop of the wine than just turning the pump on and off. I ordered the part a week ago, so hopefully within the next week or so the timer and valve will arrive from Hong Kong.