I wouldn't be so concerned about the mini mash aspect of the kit--from the looks of the kit on the webpage you'll just be steeping the grains instead of actually "mashing" them--a more complicated process than you might want to undertake for your first brew. However, the double IPA is a kind of tricky recipe to pull off--there's so much sugar in the wort that you have to be sure your yeast is really raring to go when you pitch it or you'll end up with some unfermented sugars at the end of the process. Also, it takes kind of a while (a couple months, really) for a beer this strong to really mature and taste as good as it can. If I were you I'd shoot for another IPA kit with a lower alcohol content. There's much more room for error there, and you'll still like the results.
Good luck!