6045's have had very few returned, I think the number sold is now about 700 but I haven't tallied it up, returns is under a dozen and most were repairable. These have done much better as the shaft issue was caught before any where ever made. The hole the shaft is pressed into was much tighter.
The 6025 I tallied up last week and posted here. If I recall it was 1352 sold and 73 returned, only 5 were repairable as most had the shaft fall out, the repairable ones ranged from sand jamming the drive unit or a bad drive unit or missing disk. I expect in the end about 10-15% of the 6025's will have the shaft fall out, basically if the shaft is a bit narrower or the hole was just slightly wider than spec it will come out and need to be replaced. The original design just had no forgiveness for any manufacturing deviation, as long as everything was exactly to spec it works fine. The rate of returns has dramatically slowed in the past couple weeks so I think we are around the bend already though I am sure for the next few months some of these first pumps will be presenting issues. The 6025's we will recieve from here on out should be as trouble free as the 6045's.