You do realize of course that the links to lenders on Zillow are no guarantee of the offer that they will give to you even if your credit score is 849.9? The lenders with the lowest quoted rates get the most responses. If you start actually making serious inquiries you will likely find that what I am telling you is accurate.
Of course, mortgage brokers are known to be the most reputable and well respected of all professionals... right up their with lawyers and Realtors. /s
I have used the lenders from both of those sites many times and always received the exact quote I got from Zillow or bank rate, or even better. The lenders update their numbers every day around 9am.