Since this question has been asked several times on the free pages I've decided to post the analysis over here.

Let's start with a 6D game and a TC'ed system like Hi-Lo. Normally a "one-fit-all" index is used disregarding the player's hand composition. Let's call this index: Generic Insurance's index (GII).
Of course, it's possible to generate an index for each hand composition as you'll see below.

Generic Index = +3.01 (GII)

Now, let's separate the Hi-Lo tags into four categories:

T = Ten
A = Ace
Z = 7,8,9
L = 2,3,4,5,6

These 4 categories make 10 different indices:

A,A vs A = +2.37
A,Z vs A = +2.57
A,L vs A = +2.73
T,T vs A = +3.28
T,A vs A = +2.82
T,Z vs A = +3.01
T,L vs A = +3.18
Z,Z vs A = +2.76
Z,L vs A = +2.92
L,L vs A = +3.09

Suppose the count is exactly +3 and you're playing heads up: you have 15 and the dealer has an Ace, would you insure? Obviously the answer depends on the composition of the hand. If my hand is 10,5 I won't insure but if it is 9,6 then I will.

Here are the indices for 1D and 2D:

Indices for 1 deck:

Generic Index = +1.41

A,A vs A = -2.42
A,Z vs A = -1.32
A,L vs A = -0.26
T,T vs A = +2.95
T,A vs A = +0.09
T,Z vs A = +1.31
T,L vs A = +2.36
Z,Z vs A = -0.22
Z,L vs A = +0.84
L,L vs A = +1.90

Indices for 2 decks:

Generic Index = +2.38

A,A vs A = +0.46
A,Z vs A = +1.02
A,L vs A = +1.53
T,T vs A = +3.16
T,A vs A = +1.76
T,Z vs A = +2.36
T,L vs A = +2.86
Z,Z vs A = +1.58
Z,L vs A = +2.09
L,L vs A = +2.60

If you're good at memorizing indices then go ahead and learn the above. It's also good cover when you're playing two hands.

Sincerely,
Cacarulo