First, let me say that we sell Nature 2 where I work but I do NOT recommend them to people. There are a lot of people that want 'magic in a bottle' instead of actually learning how easy it is to care for a pool properly and save money doing so and many of these do use N2!

The .5 ppm FC that the Nature2 instructions say to use is NOT HIGH ENOUGH if you want to maintain sanitized water!!!!!! There just is NOT ENOUGH residual sanitizer in the water at that level and if you have 'an event' (which could be as simple as a bird pooping in the pool or someone entering the water that is not completey 'clean' in back (it happens more than you think) then your water will not be sanitized since that .5 ppm will get consumed very quickly and the siver in the N2 has a very slow kill time. (The copper is basically just an algaecide, btw.) IF you are going to use the N2 do not let your free clorine drop below 2 ppm (assuming normal CYA of 30-50 ppm!)
My advice is forget the N2. You are paying $200/year or more on replacement cartridges for it, depening on the model, if you are replacing them every 6 months as recommended. If you didn't use the N2 and ran at higher FC it would save you a LOT of money, expecially if you are using liquid chlorine or bleach!

Also, since the N2 is putting coppper and silver in the water to act as a sanitizer that means you cannot use stain treatments or metal sequesterants since these will remove or chelate (deactivate) the metals!
Good news is that N2 puts so little metal in your water that the chance of staining is low (but it can and does happen, expecially if you don't watch your pH and let it climb above 7.8!)

Final thing, with an inline chlorinator you will want to keep close tabs on the cyanuric acid (CYA) so your pool does not become overstabilized. Knowing how and when to use trichlor properly (and more important, knowing when to STOP using it and switch to an unstabilized chlorine source) is the trick!

Your best investment would be a good testkit. I like the Taylor K-2006 (not the K-2006). Worth every penny!