Testimonials seem to be a bad sign!

I don't remember seeing testimonials on the sites of successful agents.(ie. actually sell books to commercial publishers). They will often have profiles of their authors, but that's very different.

As far as I'm aware, that type of testimonial is an advertising/sales tactic. The last thing a successful agent would need to do is advertise themselves to writers in that way. A scammy or clueless agent might, though.

Very true. I recall one time somebody asked about a particular agent here, and got the reply that she was Orson Scott Card's agent. Does she really need any comments on how satisifed Orson Scott Card is?

I can't tell much from "love me blurbs" on a website. Some are legit while others are obviosuly smoke screens.

I do, however, look for client bios, recent sales, etc... If I can't find evidence of sales that can be verified by a quick call to B&N, there's a rotten herring in Norway.