I would say about 1/2 of our upgrade kit customers send the old parts back to us, as we do pay the freight costs for this option. Worst case, we properly dispose the old parts, but sometimes we donate used speakers to a worthy cause and the best of these used parts get to see a new home. Mostly though I end up using old parts for different engineering projects.

Regarding a "flat pack" option. It is important to understand the amount of work that goes into designing a new speaker. Just the 3D CAD drawings combined with conversion to proper CAM output for CNC machining is a ton of work. We could do it, but I am not sure we would even break even on a flat pack option that would utilize the S2 woofer, combining it with - for example, the S1 tweeter + new crossover.

What would be the max any of you would be willing to pay for the following:

Flat pack unfinished Sierra-1 cabinet pair in MDF + (2) Sierra-1 tweeters + (2) crossovers + 2 port tubes?