Personally, after several tests i have rejected acrylic washes do not like it less manageable then oils or enamels and dry too quickly, the Vallejo and GW I have i use them only on bases just to finish them

For gloss surface before the washes i like Humbrol Clear (very similar to Future) with one light hand the finish is between Satin and Gloss,is easy to use strait from the bottle self levelling and acrylic...perfect for me

I actually got some oil paint today and tried making a wash from it. Diluted with some thinner and got a nice suitably thin mix that flowed well and covered quite nicely. It was also easy to clean up using some clean thinner. So all in all, the Tamiya thing was too thin, but I'll still use it for really narrow panels as it flowed really well.

I learned a ton here, thanks all for your input and help!