Expensive stocks for AK’s : useless ?

Hello,

I'm having trouble understanding something about the stocks for the AK. Let's take an example, the AK-105. Let's take 2 different stock configurations:

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– Configuration 1: basic stock + kit recoil pad / Price: 4000 rubles

– Configuration 2: stock tube + best performing stock (GEN3) / Price: about 45000 rubles

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But for these 2 configurations, the stats of recoil and ergonomics are almost exactly the same.

Config 1 : E = 56, R = 88/227

Config 2 : E = 52, R = 86/223

My question is: what is the real interest to invest in the stocks with a tube ? Is there a real benefit compared to the basic stock + kit recoil pad ?

Thanks !