All lenders are required to provide the same disclosures - a Good Faith Estimate (GFE) and a Truth in Lending Statement (TIL). The GFE gives you the information needed to compare pricing. Undisclosed lender fees are a no-no.
Most mortgages are sold either to Fannie Mae or Freddie Mac. The loan is serviced by a bank or servicing company. Those are the people you send your payments to and who escrow your insurance and property tax payments. Of the companies you list, Wells Fargo is the only one that services mortgages, unless your credit union also services mortgages. Weak servicers have gone bankrupt, but it's very uncommon. With a Fannie/Freddie loan, you will likely get someone that knows what they are doing. Servicers love to sell you stuff you don't need, so be sure to opt out of the sharing of marketing information or your mailbox will be stuffed with offers for strange insurance products and credit cards. Servicing contracts are shorter than the life of the loan and servicing companies are often sold. You may have multiple servicers over the life of the loan.
Ditech used to be the on-line subprime arm of GMAC Bank IIRC. Their advertising budget during the bubble was huge. A lot of the on-line brokers are cheaper because they don't maintain retail offices and run assembly line operations. If your loan is simple, the process runs smoothly. Not so much if you are self employed and/or have credit issues or the like. Credit unions tend to be slow in processing paperwork, but it depends on the credit union. Get some recommendations and shop price (rate, points and fees) until you are satisfied with the lender and the terms.
Don't forget to check PenFed credit union. They are usually one of the cheaper options.