I just did a bunch of goldsmith synths, and found myself using 2 manipulations instead of a master's mend II quite often.

Positives:
  • it's an extra step, an extra shot at ToT, chance to extend the synth to get in a 3rd CZ
  • it's versatile, you don't need to be at 10/20 durability, which can save a step of SHII
  • it can keep you from capping out CP if you get a lot of ToT procs early

Negative:
  • it costs 16 more CP

When I had SHII wear off at 10/20 durability, I would use MMII. But since I don't need reclaim anymore, I'm putting Manipulation in its spot. Just something to think about for my fellow crafters.