When installing your laundry equipment under a counter top make sure you give the dryer vent consideration. Adequate ventilation is critical on all dryers regardless of the installation. Its easy for the venting to get crimped behind the dryer as people will try to force the washer and dryer back as far as they can get them either for more room or to try to make it a flush installation with the counter top. Once in place it's also more tedious to remove the dryer to clean behind it with this type of install.