I largely buy used microscope equipment, built decades ago for decades of use, from sellers who often do not know what they are selling and, once in an unavoidable while, from sellers who do know and are not forthright about their wares.
I know nothing about Vision Scientific, but looked over their website, reflected on my experiences and imagined how things could go. I, myself, would look elsewhere. I found too many ways I could receive a pig a in a poke and pay for the experience.