Personally, I'd say go for it. Stay within the limits of the game and give some people warning about what you're doing, but for the love of all that is and isn't, save the bloody time.
I have no problem with folks who keep things reasonable,
even though it is apparently ridiculously easy to breed pokemon in X and Y to have max IVs due to pokes caught from a particular location being guaranteed to have at least 3 perfect IVs, and EV training takes at most an hour the slow way thanks to the super training and 10-20 minutes with hordes and proper equipment.But when people use nothing but ubers it annoys me. Where's the sport in that? When people use nothing but shiny ubers with obvious maxed stats and helpful natures it's ridiculous. With breed-able pokemon it's perfectly reasonable to come up with these kinds of maxed out stats thanks to skilled breeding in less than a day, in X and Y less than a couple hours. If someone wants to hack that and save them time fine. I admit I have done it before, but I find the hand training and breeding more satisfying.
But when people start doing that shit to stuff you get
at best once per 20+ hour playthrough, that are specifically disallowed from breeding, and are already stronger than most things that aren't another uber even without perfect IVs. That pisses me off. Not only is it a cruise control to victory with no effort, it makes the few people who legitimately get lucky, and get good stats on their 'one time' pokemon look like hackers themselves.