if you're planning to spend $ on the carpet (surface layer), then you should plan to spend $$ on the under layer. a good under layer will let your carpet last a lot longer. when you walk on carpet with good under layer, you'll feel a lot more comfortable too. 2 M( W% v3 y# E& t0 ` 1 a" u% G) y' M+ N, pof course, this all depend on how long you plan to live in this house too., R+ y6 z6 Z& q" |; e