Dennis, you can figure the oilless compressor at approximately one-tenth the lifespan of a good compressor with oil in a crankcase. Now how much are you going to use it? And especially how long will you run it continuously when you do use it? For many people the oilless is a good way to go; less cost, no oil to mess with, etc., but I think you'll find in the manual that you should not run it continuously for more than 10 minutes at a time. Actually, you'll find the same warning in the manuals for some of the aluminum compressors with shallow crankcases. I carried a small oilless compressor in the RV when we were traveling and it was just fine, but when I quit traveling and had a big shop building, I bought a big oilless, and it never made more than 8 months without breaking down and sometimes only 2 or 3 months. First time it was broken reed valves, next time needed piston and cylinder, next time the cooling fan broke loose and cracked the cowling, etc. But I was running it a lot! And of course, I got rid of it and bought a "good" compressor. Now the good part about the Sears oilless is that they come with a manual that includes a parts list, and it's relatively easy to completely rebuild one in less than an hour.