I have refied a few times and every time I tried one of those online companies they either couldn’t deliver what was advertised or the service was very poor and time consuming. I always ended up doing business with one the big banks in town (BofA or Wells Fargo) where I had a loan officer personally working on my refi. I may have paid a little more but the process was done more efficiently. In general, if it looks too good to be true it usually is.