Keep in mind that the IPV5 TC for SS is 304, not 316L like everyone else. It still works with 316L coils, just have to fiddle with the temp. It can also do custom TCR's but I haven't messed with that much.
The great thing about the G2 is you can just use xXx mode which is all metals mode. No need to switch between all the metals, in fact the other settings are not necessary for me and plenty of others, just xXx and power mode is all I ever use. Once you get the hang of it you can adjust FSK pretty easily, for SS my FSK is usually between 13 and 17% depending on the build and if I want a hot or cool vape. For Kanthal it is lower, usually between 2.5 and 6% FSK. If your not switching between different tanks a lot it is easy to remember which FSK works best for you.
I wasn't a huge fan of TC until the G2, now I only use TC with all my tanks and drippers on the G2 and in power mode it kicks like a mule. The G2 really is a game changer for TC, it has changed my perspective on it in a HUGE way. It works better than any of my other mods for SS TC by a long shot when in xXx mode and with Kanthal it is just as good. I have never tried Ni or Ti with it, I don't like using those metals, but I bet it works just as well.
If you like TC then get the G2, it really is worth twice the price and then some. If you're fine with just power then the IPV5 is a beast and the fit and finish is awesome. It is really that simple.