had a propane truck where i worked during high school, you could go a year and still read the writing on the dipstick thru the oil.
i havent had any experience with the compressors but it could benefit you if you convert your fleet or buy new stuff running on CNG. There are lots of tax breaks and benefits out there for going to alternative fuel.
I'm a big advocate of CNG, and replacement vehicles will come with cng from now on.
this was my neighbor for a few months...
Deep South Lawn Service
2003 dodge 2500/ cummins
20' landscape trailer - 6.5x12 landscape trailer
5x10 utility trailer
3- 60" lazers, 1- 72" lazer 1- 36" W/B
15 shindaiwa handhelds, 3 echo saws
36" stihl chainsaw
2 fs100rx's, 2 br600 magnum FS94R, KM90
'92 long 2360/6'king kutter w/7.5x18 trailer
lawn sprinklers save your grass, fire sprinklers save your -----