Hi! The decision itself is worth a congratulation, that you want to quit the stink stick!
I completely agree with @Arpee, fellow vaper, on everything! Especially regarding the nicotine amount! It’s better to have it stronger from which you can reduce later, than to get cravings.
My wife uses the Ursa Nano and I also used Ursa pod heads… In terms of flavor and pod head durability, I really take my hat off.. What’s negative is that it’s not a product that lasts from 5 AM to 9 PM.. the battery won’t last, and since it’s only 2.5ml, you’ll obviously have to refill it a few times.. What I didn’t like about it was that the liquid level is hard to detect, and also that the cotton opening in the atomizer is very high up… It definitely has a name 
so you really have to refill it often because it quickly reaches a critical level… even though there’s still liquid in it.
That’s my take on the negative side of the Nano..
The two mod-kits you mentioned are mainly DL devices. So, first of all, you need to decide what you want…
DL: direct lung hit with lots of vapor
MTL: inhale like an analog cigarette.. first into your mouth then from there to your lungs.. here the vapor is smaller.. the two paths are completely different..
So, in my opinion, this is the most important question first, if we know that, then we can talk about the devices 
Unfortunately, I don’t know the site you mentioned.
Happy Vaping and welcome among the vapers here