I assume you mean less than 20% down payment. Yes, it makes sense since the VA offers a good rate, but you should compare loans if you want to put down 20% vs 0% with a VA loan. I like to sleep at night and having a lower monthly payment allows me to do that. Having that 20% in the bank these days at 1% or less means little unless money is tight. If you can put down 20% and be comfortable doing it then look at conventional and save your VA entitlement for the future when you might need it. All situations are different so shop and compare.
Your question does really make sense, but simply put the VA loan is one of best loan programs out there. I am current looking to buy a home and I am going to use my VA entitlement. The VA loan offers $0 down, low rates, and NO monthly mortgage insurance. Only way to get out of paying PMI or MIP/MMI is to come up with a lot more money. And most people don't know this but you can get more than one VA loan. It's called 2nd Tier Entitlement. So why would you do anything other than a VA loan and save your money for a rainy day?
VA Loans are expensive Loans. You will typically finance more then the value of the house because they roll in all the fees into the mortgage hence the 100% financing. Not sure what you mean by 20% interest? If you mean 20% down your better off doing a conventional loan. If you have money to put down up to 3.5% your better off doing an FHA. But VA is a Solid Choice for no Money down. But you still have an origination fee of 2.5%. Choice is yours. I'm you have found a house by now? Call with questions. --307-772-1184