Howdy, all! The guitarist in my band has a '71 SG that he bought in '72 and it sounds real sweet. It has what appears to be a Bigsby B5 vibrato, although it doesn't have the big logo. How do we determine if it's a real Bigsby or an aftermarket? I ask because it is missing the handle, and thought maybe he'd want to install one. He's less than enthusiastic, stating that these vibratos have a bad reputation for not staying in tune. Is this true, or is it merely a matter of correctly setting it up?