I usually inform those that have purchased Monster products to try to avoid them due to their frivolous lawsuits for starters then move on to how there isn't any quality differences from Monoprice, Blue Jeans etc. compared to those that they bought, it generally works.

Jason
M80 v2
VP160 v3
QS8 v2
PB13 Ultra
Denon 3808
Samsung 85" Q70