As an ex-Tit, current-Plt I agree with most of the opinions, that while Tit is very nice, but it's not worth to go out of your way to achieve it. Short a couple of nights - sure thing, do it. Short 10-15 nights? Only if you can get very cheap rates somewhere - already at $ or €100/night it's a waste of money, you'll never get value of 1-1,5k worth over Plt.
In SEA & EMEA I got excellent suite upgrades both as Tit &Plt with a very good hit rate (90%-ish I reckon)