*gearspeed:

if you will be using the van mostly daytime, seldom at night: CS5 on all the windows.
if you will be using the van day and night: CS20 (or higher VLT) on windshield, CS20 on front windows, CS5 on the rest

regardless of brand or series, madilim ang 5% VLT sa gabi. kahit 20/20 pa vision mo. dahil 5% visible light na lang ang pumapasok sa glass mo. how much worse kung umuulan pa. super dilim na yan.

sa umaga, wala problema sa 5% VLT. sobrang maliwanag ang araw kaya kahit 5% visible light lang pumasok sa glass mo, kita mo pa rin ang surroundings mo.

for safety at night, recommend to use 30% VLT and up sa windshield, 15% VLT and up sa front windows. 5% VLT sa 2nd row and the rest is acceptable.