Your stitch gauge is the important one. If you get that correct, then you can adjust for the length. Most patterns say to knit for X number of inches, anyway, so you don't have to worry about the row gauge.
You can always knit fewer/more rows to get length, but you can't adjust the width, so that's the gauge you want to be right on.
"Trust the pattern!"
Time flies like an arrow, but fruit flies like a banana.
Hop aboard while we follow the cloud-covered van of knitting harmony, man!! Woooo!! --Hedgehog
IngridKH on Ravelry