I recently acquired a Decent Espresso machine and one of the profiles that seems interesting is the 'adaptive profile'.
It states that 15g should be used but I've been using a 17-19g basket.

Is there truly a significant difference between a 17g and a 15g basket for a 15g dose?

T

Headspace and puck depth together make a significant difference. But if you dose 18g in your 18g basket, headspace at least will be the same as 15g in a 15g basket. Your puck depth will be deeper though, so there will be "some" difference. Just not sure how much. Maybe try 18g dose in 18g basket before making any purchases?

Anecdotal, but in my experience, underdosing my 17g basket at 14-15g results in shots pulling significantly faster. Anywhere from 16-19s vs 25-30s. This is a very narrow 52mm basket so the change in headspace/puck depth is more pronounced vs a 58mm.

Baskets make a difference.
You can't have too many of the same size with varying profiles.

benhb wrote:But if you dose 18g in your 18g basket, headspace at least will be the same as 15g in a 15g basket.

Nope. Depends on the profile. Faema ≠ La Marzocco ≠ Synessso ≠ IMS ≠ VST