We use AAMI for both cars and house/contents.
Foz cost us ~$700yr full comp agreed value for $24k. Nominated excess of $1250.
I am 32, wife is a cradle snatcher at 33.

Nominated a value slightly more than the finance owing, it helped massively as we found through our experience.
Also like to bump the excess up to a reasonable amount, figured these days it costs at least $1k for any significant fender bender repairs or worse if it is our fault.
They don't care what mods are done to the car as long as it's nothing to "extreme".
For the less "enthusiast" types of insurance like AAMI, you're better to hedge your bet on specifying an agreed value of what it would cost to replace your car with all the fruits if you lose the lot. Seemingly is the approach most are having these days rather than nitpicking over specifics, unless of course said mod attributed to the damage/loss of your car.
Eg, coilover strut snapped and caused loss of control, spinning off into paddock, clipping a tree and shirley the cow landing on your bonnet.
We had to make claims against our policy in late 2015 and mid 2016.
2015 claim wife backed into another car, caused a quoted $2k of repairs to a $4k car.. (Mazda Eunos 500X) she punched a small hole in the rear door with tow ball. They replaced the whole door. Was about $1k repair/repaint ours.
2016 claim at fault driver rear ended the wife, caused total loss to our car and hers, and was not insured.
We didn't have to pay any excess at all, it was all put on the other driver.
Other than proceedings being very slow it all went through without issue.
Took a solid 6 weeks from incident to settlement/payout.
In both cases we were given a list of their preferred repairers to choose from for our repairs, rather than being forced to "like it or lump it".
Hope all that dribble helps!
Would be nothing worse than getting a "good deal" from an insurance company only to be loop-holed out of the policy you've paid for come the time of having to use it.