Air shocks went out on the back do i replace the fronts ones as well

I own a 1999 Deville. I had only the rear shocks replaced as well as the lines and the compressor used with the shocks. I purchase only original AC DELCO equipment. The total cost for the labor and parts car was about $1600 dollars at a shop I regularly used. I been using this shop for about 15 years. Their labor is $70.00 an hour. The compressor alone was $600 from a Cadillac dealer. I would not go to the junk yard for a used compressor. There was no after market compressor about 8 years ago when I had the complete rear air system. I purchase this car in 2003. The shocks are still find today. There are several 1997 through 1999 Deville's in the area. Their cars were replaced with other types of shocks because of the expense. However, you should see how high some of the vehicles rear ends are off the ground or how low the rear end are near the ground. I left the front shocks alone because both were okay. However, I had to replace them a couple of years later at the same time. I plan on keeping my vehicle a long time. I personally believe there is not a better riding car out there. I spent part of 2017 and 2018 checking out other new vehicles as well as renting vehicles. The comfort and gas mileage is just not there.

KENRBROWN answered about a second ago I own a 1999 Deville. I had only the rear shocks replaced as well as the lines and the compressor used with the shocks. I purchase only original AC DELCO equipment. The total cost for the labor and parts car was about $1600 dollars at a shop I regularly used. I been using this shop for about 15 years. Their labor is $70.00 an hour. The compressor alone was $600 from a Cadillac dealer. I would not go to the junk yard for a used compressor. There was no after market compressor about 8 years ago when I had the complete rear air system. I purchase this car in 2003. The shocks are still fine today. There are several 1997 through 1999 Deville's in this area. Their cars were replaced with other types of shocks because of the expense. However, you should see how high some of the vehicles rear ends are off the ground or how low the rear end are near the ground. I left the front shocks alone because both were okay. However, I had to replace them a couple of years later at the same time. I plan on keeping my vehicle a long time. I personally believe there is not a better riding car out there. I spent part of 2017 and 2018 checking out other new vehicles as well as renting vehicles of similar size. The comfort and gas mileage is just not there. Also, many of the newer vehicles come with 4 or 6 cylinders.