On a number of levels, it changed our relationship for the better in a huge way.
My first BBC was by far the biggest cock I'd ever taken. While I'd thought I was happy with sex before this really opened my eyes as to how good it could be. I became obsessed with taking huge cocks pretty quickly.
As for our relationship it had so many benefits too. Me and hubby were both naturally submissive, now that I was being taken care of by alphas he could embrace his sub side too instead of 'pretending' to be dominant to keep me happy. Also, we started the lifestyle pretty young (early 20's) and the feeling of doing something so taboo and exciting only made our love and trust in each other stronger.
In short, it's the best decision we ever made.