doing costco laminate , do I really have to buy the harmonics brand underlayment?

[willydog]

Can I use a similar after market underlayment? I'm not too worried about the warranty, unless there is some compelling reason to use the manufacturers underlayment. I can save a little money with a third party product. Any thoughts?

[Edwin Pawlowski]

Sure, as long as it is equal in specifications. How much will you save?