I need the truth about wheel adaptors

Seems there is not much of a selection when it comes to finding a 15" SBP wheel to fit my Duster. i currently have SBP 14 X 5.5 ralleys and would like to put on something wider but I am limited to the selection of 14" tires. There is a good selection of LBP 15" wheels but I would need to change to LBP on the car. So, my question is, how reliable/safe are the adaptors to go from a SBP to LBP?