Sounds reasonable for them to be cautious. Do we know if the ZS EV has no tint to any glass and is 100% clear from factory ? Global Tint have assured me the fronts can be done legally to 70% with UV/heat protection and give a written guarantee.
Although the glass on the ZS EV is deemed to be clear / totally untinted.
Due the glass manufacturing process, no glass is completely clear.
I guess the glass in the ZS EV is about as close as your likely to get, with regards to clear.
Try this, put one of the front side windows down about half way, then place a sheet of white A4 paper behind the Inside of the glass.
50% behind the glass and 50% above the glass.
Now tell me that the glass is completely clear !.
I decided not to restrict visibility through the side windows at all.
Legally the rear side windows and screen can be as dark as you like, but don’t go to dark IF you don’t intend to go with tinting the fronts, otherwise the contrast could be to great.
My installer said that the small tiny windows in the rear quarter panel was a pain in the bum to get right.
They took longer to get right than any of the other windows.
The access is so limited.
When I declared my tints to the insurance company, they did not load the premium and they are itemised on the policy.
They never asked how many windows have been tinted strangely enough.
Some companies will not allow tints, some only permit the rear glass to be tinted, others are more lenient.
I would check first with your insurance company before going ahead, is my best advice.