Whirlpool Duet Dryer Review

I purchased a Whirlpool Duet Dryer the first of this year (2009) and have not been completely satisfied.  The clothes usually do not get dried even at high heat for 35-40 minutes.  This dryer has been advertised as drying in just over 30 minutes.  I do admit the exhaust hose has a curve in it, but would this be causing the problem?  I had purchased my other dryer as used for $75.00 in 2001 and it was working fine, drying completely, except I was concerned about electricity efficiency.  Now, I'm worried even more since this is a new dryer and is supposed to be energy efficient.  Otherwise, I do like the dryer.