Heck yes get the valve!!! I can't say it saves a lot of time, but it is definitely much much nicer.... sort of a big luxury....
Racking canes melt unless you use metal. The metal ones get hot to the touch. They also sway around, tending to pick up sediment from the bottom. Racking canes are smooth, requiring a really tight tubing around it which is difficult to get off and clean, or a loose fitting tube that will tend to suck in air unless you use a circular clamp on it... which now means you need a screwdriver on brew day... Oh and don't forget, you'll need to start the siphon...
Sure, none of those are big problems... just a few more little things to deal with. And frankly, for me, it was some of the most annoying things on brew day. I hated starting the siphons, I always had a problem with racking canes sucking in air where they meet the tubing. I cracked one plastic racking cane when tightening a clamp and I melted another one before going to the metal ones which get really hot to the touch.
But with the valve, you just attach a barbed fitting, and you're set forever... just stick the hose on there and start draining the wort from an inch or so above the trub.... perfect every time! No messing with racking canes and siphons...