AndyinTexas wrote:...Do water and dissolved solids really wear out the baskets? ...

I would guess that the un-dissolved solids, e.g., ground-up chaff, would do the most wearing.

As a data point, I just pulled out a couple Rancilio baskets - the 40.100.010 part number used on older Silvia's. One was from a nine-year-old Silvia that, given the machine's pristine condition, was not used very often. The other was used in a light commercial application for about five years. The holes in the commercially-used basket are much larger - when held up to a lamp, the difference is clearly visible to the naked eye.

So, assuming that the two baskets were the same spec new, then baskets do wear. However, I haven't tested these baskets to see what the difference is in terms of grinder setting or taste - actually, I haven't used these baskets at all, as they both looked worn out (in other respects) compared to newer baskets that I have (different part numbers so not comparable).

My plan is to pick up a replacement VST 15 basket (the 58mm basket that I use the most often) in a few years. Then I'll see if there is any difference. If not, then I'll put the new basket back in its box, and keep using the old basket.

YMMV.