Here at Matanuska we are using Pegasus 1005 with very positive results. We are going on 30K run hours and the oil is testing as good as new. When we picked 1005 we found out that it is formulated for gas reciprocating engines and the oil performance proves that it works. We test our oil every 500 hours and the TBN has gone from 5 on the new oil to 4.4 after 30K. If you need more information contact me and I will share sample results with you.