Let's assume that NFCU greets you with open arms and that you qualify for all of the loans. If that's the case, you still need to crunch those numbers into a mortgage calculator (like the ones at http://www.navyfcu.org/calcs/index.html
) and figure out how the monthly payments affect your budget.
Any loan of more than 80% of the home's value will require an escrow account and you won't be able to invest those funds on your own. IIRC NFCU will want two months' property taxes & home insurance up front and will continue to raise your monthly escrow payment by their estimate of inflation in property taxes and insurance fees. They may want lower deductibles on the insurance and you may end up paying a higher premium than you wish. So if you're getting a 100% loan then your closing costs & mortgage payments will be higher than just P&I.
You also need to check whether or not NFCU requires PMI. It used to be required for all loans over 90% but they may waive that for a VA or even a qualifying FHA loan. Again the 100% financing may have that additional PMI payment into an escrow account.
Note that your interest rates come with some fine print: "Rates quoted below require a 0.75% loan origination fee. The origination fee may be waived for a 0.25% increase in the interest rate."
Generally, paying points up front is a losing proposition. You're betting the mortgage company that rates during the life of your loan won't go any lower, and they're happy to accept that bet because you'll pay them even more money to refinance when you're wrong. Even if you're right, they'll make their money off the spread of investing your points (instead of letting you profit from keeping that money).
When you don’t have a low-low interest rate, I tend to favor a lower payment. This is especially true if your monthly mortgage payment is coming from your savings or something less reliable than a U.S. govt pension. The 20% down with a lower payment will save you a substantial amount of interest over the life of the loan and will free up additional cash flow for whatever you want-- investing, emergencies, fantasy vacations, your choice. You could even pay down more of the principal with the extra cash flow or you could boost your funds with a HELOC.
The 100% loan will not only have a higher monthly payment (plus the PMI and the loss of the use of the money for the escrow account) but you won't have any discretion over its use. You'll have to make that monthly payment EVERY month whether or not you had a temporary cash-flow crisis.
As Nun mentions, another issue is how long you'll be staying there. If you're owning fewer than five years then you probably will pay more in closing costs (on both ends of the ownership) than you'll build in equity. This is especially likely in a topped-out market. The median period of home ownership between moves is only seven years, so you have to decide if this is your final home or if there's a risk that your company (or you!) will want you to relocate to enhance your career.