I can't tell from your link what model of
ecig the Veppo is. Maybe someone who knows will chime in.
You get better vapor from a higher concentration of VG in your
juice and/or a stronger ecig. I think the one you have is fairly weak but again, I can't be sure.
If you are having trouble tasting the liquid after three hours, it could be that your taste buds are still fried from smoking and will need some recovery time. Also, continual
vaping of one particular flavor may dull it. Do you have only that one flavor?