What is the upside of reaffirmation of my mortgage?

There is none. Don't re-affirm a mortgage, ever, no matter what.

It is extremely unusual to reaffirm a mortgage debt. There is no compelling reason to do so.

The upside of reaffirming your mortgage is that you get to keep the home and some or all of the equity that there is in the property.

I practice in Colorado, and every jurisdiction is different. Having said that, there is no particular benefit to reaffirmation of mortgage, IMHO.

The up side to reaffirming a mortgage, is that you may be able to build your credit again with the particular lender. As a lawyer, I do not se much up side in reaffirming debts, however, a house is a little different. It is not totally clear, and the law is not settled, but the creditor could possibly accelerate the loan because many contracts call the filing of a Bankruptcy a technical default. Their is another school of thought that says, you can not foreclose on a house if the purchaser is current in payments. Their seems to be some conflicting laws and precedent. But in general, if you are underwater on the house, you may want to re consider your options.

Reaffirming a mortgage debt is usually a bad idea. You lose the protection of the discharge is you cant fulfill the terms and conditions of the reaffirmation agreement. You can still accomplish the goal you stated in your quedtion by paying per the original contract.

If your home is worth less than the mortgage balance I would not reaffirm.