I haven't stayed in The Star Inn but I stayed in Maxim's Inn at the bottom of Soi 7/1 and it wasn't bad at all for the money. It's a great soi to stay in if you ask me. Not too noisy and not too boring and close to the skytrain and everything else.
Can't remember how much I paid, it was 2 years ago but anyway I think a good choice of soi.