Like anything, it's all relative to where you are coming from. I'm from the USA, so:
Air Quality
Kunming has some of the better air quality for a tier 2 city in China. However, this year is worse than most due to temporary (drought) and trending factors (cars, construction). So good for China, but still not better than LA, and not even close to Portland/Seattle.
Internet Speed.
Long story short, if you can get China Telecom dsl in a new building, there is a good chance you can get the new 6,8,12 mbps dsl. I currently use the 4mbps dsl with a good vpn, and can max out my dl speed to the US. If you use other companies or have a lan or cable based solution in your complex, then it varies a lot.
Black Outs
No black outs. Prior years some very minor brown outs for certain districts. Power loss is pretty rare, and would primarily be due to storms and downed lines. What you need to worry about currently is low water pressure. Parts of greater Kunming experience water outages. It's variable as to where and why. See this forum for more info: www.gokunming.com/en/forums/thread/5697/water_rationing
Suits
Suits can be made, but Kunming isn't known for it's high end tailoring. High-end men's shopping is pretty limited. Of course you could jot over to Hoi An, Vietnam and get a world class colonial days suit made for $$. I'm not the expert on suits here, as I brought all my own.
Is it safe at night?
Violent crime is very rare. Much less than USA. Petty crime doesn't abound, but it can happen as being white will increase your chances of pickpockets/purse snatchers. But overall rating, is in the high to very good for personal safety. Being male helps, but that's not specific to China.
Bonus. Electronics
You need to bring all your fancy toys and accessories and anything else you sort of been wanting. Kunming electronics shopping is limited in choice and pricing isn't great.