I�d like to ask how much could I win (or lose) if I switch from Hi-Lo to 10-Count to achieve a better (100%) IC. The game is 6D, S17, DA2, DAS, ES10, ENHC, but it has one weird rule � one is offered insurance every time the dealer�s first card is 7 through Ace. This is 8/13 or 61.5% of the time. Thus, using the insurance bet can be very profitable when the proportion of tens is high. That happens about 12% of the time. So, the absolute percentage is 0.615x0.12=0.074 or 7.4%. I am flat-betting and using a bonus that gives me an advantage over the house anyway. So, I am not interested in BC. Using 10-Count for insurance decisions is explained by Stanford Wong in his Professional Blackjack. Every ten card is assigned -2 value and any other card is given +1 value. Thus when RC is more than 24 (for 6D) it is profitable to take insurance. Will my playing decisions suffer a lot if I use the obsolete10-Count? I could recalculate 10-Count RC to Hi-Lo TC to find the critical indices. Playing Efficiency (as defined by Griffin) is not relevant to unbalanced counting systems and is only an estimate. But how bad an estimate? So, what is better? Hi-Lo with PE=51% and IC=76% or 10-Count with PE=?% and IC=100%, taking in account how often the insurance is offered?