The Milwaukee impacts are powerful but the variable speed trigger isn't that variable and eventually starts working intermittently. After a year of daily site use the brushless motors seem to give up the ghost as well. At least in Canada Milwaukee will not honor the warranty if the impact shows signs of excessive use (they consider it abused). Therefore if it's a shop drill you shouldn't have a problem with the warranty but a site drill essentially doesn't have one.
I ended up switching from Milwaukee to Hilti after getting frustrated with the unreliable trigger and lack of warranty. I'm also invested in the Festool battery platform so I'll be getting a Festool impact once they are released.
I use my Milwaukee impacts daily, both on site and in the shop. The M18 Surge had problems, sent it in with free call tag, was fixed for free, and sent back for free.