Hey Tony,
I have had a Hornady L&L Auto Progressive since they first came out nearly ten years ago, and the only part I have replaced is the case retaining spring which can get chewed up if you are not careful changing shell plates. Hornady sent me two replacement springs for free, but I have yet to chew up the first replacement spring.
As far as its priming system, I have no problem with mine as long as the machine is kept clean. If spilled powder gets in the primer raceway, it will jam. It works fine as long as it is adjusted properly and kept clean. I do use wood dowels in the primer tubes to insure the last primer is forced into the primer shuttle. I also use dry graphite lube in the raceway to smooth the movement of the shuttle. I think the L&L primer system get a bum rap by folks who simply cannot understand its workings.
For years, I never bothered to utilize the Lock and Load feature of the press. I simply changed all my dies when I changed calibers. In recent years, I have purchased additional bushings for use mainly on my sizing dies. Because of changes in bullets or crimping or whatever, I still don't have much use for leaving bushings on seating dies. This would also be true if I used the Dillon head change method. With the Dillon, however, the heads are a lot more expensive than one or two Hornady bushings. I have not had any bushings loosen for me in the past five years or so.
I also have found that a few dies will not work well with my L&L press. The problem is that the head on the L&L is so massive that some dies are too short to reach through the head far enough. That is not true of all my dies, just a few calibers presented such a problem.
If you do need to use all five stations, the ejector wire at station five will interfere. In that case, you can simply move the ejector wire up and out of the process, and then you will have to remove the finished cartridge by hand before you put an empty case in its place.
The L&L is high quality and produces a good product. You can also add on a case feeder like the Dillon 650 add on, but that idea does not excite me. I like it. It works well.
Best wishes,
Dave Wile