router is for sharing connection easier,

for signal, u need to tweak your modem TX power,

or use reflecting signal method ,

and find best spot in your area,

best signal = dont guarantee best speed

best speed = dont guarantee best signal 

well,

if u are just want to plug in your modem and direct share the connection & dont mind the TP LINK stock firmware at all, then of  course V2 will be good due to support 3G & 4G both

while if u know a little bit about openwrt ( linux ), then u might want to get V1~V1.3 version, as V2 dont support openwrt firmware for now,.

depends on personal preferences,

for me after i try both TP LINK & Openwrt firmware, i would rather stay with Openwrt 

just my humble opinion