You bought a new vehicle, mention it right away and don't take no for an answer. I had to fix a charcoal canister and fill tube on my Chrysler Aspen after the warranty was over, and it wasn't cheap! Same exact issues as you are describing.
Nothing to worry about here, once the tank over-pressurizes from heat there is a relief at the bottom of the cap towards the engine.
Some steam will come out over a period of time, you wont see it or notice it. Just top it up every few months and you're good to go.
Here is a picture of where...
Tomtop isn't a very good unit, why not wait a few months for a properly R&D'd and tested unit? Unless you earn enough to afford both Tomtop and Raxiom, I'm sure it'll be worth the wait.
I vote no, its not uncommon in the Audi community (where I came from) to upgrade front bumpers and rear bumpers to Ultra sport models or S series bumpers. As long as you remove any badges I'd say it would be a great mod.
I work for a manufacturer, software engineering and testing takes a LOOOONG time, and even then, there are issues to be resolved.
I'll still buy it after I turn into a skeleton, no worries.