The U.S. economy appears to be on the mend. In January, the Manufacturers Alliance for Productivity and Innovation gave a tentative thumbs up to sustained business expansion through the first half of 2013. And the Institute for Supply Management's manufacturing index rose again in January, painting an optimistic picture. Maybe it's time to buy that machining center you've been thinking about.\r\nBefore you whip out your checkbook, though, some homework is in order. There's a lot more to machining centers than spindle speeds and rapid traverse rates. Sure, you've had good results over the years buying machines based on that, but that might be the wrong criteria in this brave new manufacturing world. You're facing growing competition from overseas and down the street, so you owe it to yourself to take a look at what's changed in the years since you bought your tried and true 20"×40" vertical machining center.