The main pros.: the band doesn't depend on particular distribution. It fits to any type of random variables. Also it allows to calculate bands for instruments with extremely high volatility.
Cons.: formula provides a rough estimation in some special cases like lognormal distribution.
In true TradingView spirit, the author of this script has published it open-source, so traders can understand and verify it. Cheers to the author! You may use it for free, but reuse of this code in a publication is governed by House Rules. You can favorite it to use it on a chart.