math hammer

its not an exact science but it can be used to decide how effective a unit can be before you deicide to either use it or buy it.  so iv math hammered a few new chaso units to decide there viability

firstly the  process 
i take  a unit  like  the forgefeind with  standard gear which is 2 hades autocanons  then i have 2 decide what im firing at  now i chose  AV12 (av 11 would increase its efficeincy also 12 is the middle ground)  and  against 3+ and T4 armour as most people play marines and its ap4 so no point choosing a lower AP value

so here is how it works   u roll 8 dice take away the misses  with wats left work out if u penetrate or glance the armour value u want then with the same dice check the wounded the T u wrote down if their are any fails remove them then roll for armour saves and write down failed saves so you end up with something like this
hits p/g av12    3+ save T4
5    2pen          2wounds
4    1g1p          1
4    1g1p          0
 4    1g1p         0
1     1p             0
4      1p            0
1      1p            1
6      2p1g        2
4      2p1g        1
4      2g1p        1
3      1p            0
6      4p            1
6      2g            2
4     2g2p         3
4       1p           0
2       0             1
4      1g1p        2
4      2p2g        1
6        1p          1
7      2g2p        1

 an average from this would be 4hits  1p 2 wounds

from this we can see that the forge feind should be used for light armoured vehicles and light troops you could change that to 3 ectoplasma  canons str8 ap2 then it can be used to take out infantry light or heavy

the next one  is  flakk missile from the havoc

using the same process

4  1G
4  1p
4  2p
3 1g
3 1g1p      

over  3 games an average would be 3 hits  1p

obviously this is not a sure fire thing  but helps to give an indication of how gd a unit will be