You don't provide any evidence that the synthe has any of the benefits you mentioned.

It is actually only one ounce lighter than the giro indicator:

Giro Indicator Bike Helmet - REI.com

The indicator also has 20 vents vs the synthe's 19, so your claim that a more expensive helmet has more vents is incorrect.

So, the indicator, which cost me $20 new, is 1/12th of the price of the synthe, has one extra vent, and weighs within one ounce of a helmet cosing $225 more.

You provide no evidence that the synthe is mips certified, or has better straps, or provides a more accurate fit. Both are the same weight and the indicator is better vented. You have no evidence the synthe is more aerodynamic.

Both helmets have a 4.5/5 rating.

Try again.