Trond,
If you are mindful and neat and take your time trimming the Fan Shroud, I can assure you , you Will Not have any issues regarding excessive heat build up. This isn't a factor with running this power plant, as far as the Velocity Stack consider it as a little mini super charger ( Increases Velocity of the incoming air while decreasing the pressure ) basically optimizes performance, will it run without it, of course ! Will it hurt the engine if you don't run it? Of Course Not. But if you are in fact a 3D smack kinda guy, then you definitely want it installed. Based on your flying style, you aren't missing anything not having it installed.
Lastly , something that I have always kept in mind when trying to decide what equipment I should run to include what powerplant to choose. ( The motor of choice for the N7 is the OS 105, Matt runs it with the Velocity stack installed and flies his machine without a single issue, I can assure you if there were ever a doubt regarding lack of cooling due to modifying the fan shroud, he would have designed it differently. )
Hope this helps as well. You have a nice machine, and it will serve you well.
Best Regards,
Kevin