Typically I preface it, if I do this at all. If I know someone that has worked with them, that's a huge selling point. If I've met them and spent time with them in person... even bigger. To me, the wedding industry is all about character. Sometimes you truly CAN tell that by reading a person's blog/website. Sometimes it's face to face contact that leaves an impression. It's always quality of work. I'm fortunate enough to have a large pool of vendors that I've worked with in the past to chose from. I have incredibly high standards for myself and co-mingling my name with anyone's name in ANY capacity can be scary. I also let my clients know up front any known issues with vendors that I still recommend [ie. "she's amazing, but really not so great at email... we'll just have to pick up the phone and call her"]. I believe honesty is key!