I think the leads that come in from people reading reviews are a way more valuable lead. You and the client are somewhat on the same page with expectations and the client doesn't feel like you are a complete stranger, they know something about you in a way. I find people who mention they hired you because of reading reviews are much friendlier and welcoming. A lead that you got through a marketing campaign can sometimes have that Contractor Wall up, feeling like you are just another shady contractor out to rip them off.
I do think that a lot of people are a mix of both. Someone who needed a service and searched for it, found your company then did some some research about you and your reviews.
