Is it worth it????
I’d say get to work on all the other parts of it. When you have all the ingredients for it, either buy or gamble.
In no way are rates good for mystic forge precursor attempts, not in any sense of the word “good.” But they have stated they’re making them easier to get, such as dropping more frequently.
Save up the 128 gold.
My advice, save up the gold. Mystic forge is a huge gamble and there’s a big chance you’ll loose all your money in there and never get anything.
Wait for the next event!