I do remember. Since then the search underwent an update and some optimizations. I'm releasing another version this weekend, which includes even more speed optimisations including an index table.
I have added some of these optimizations via ftp you gave me. The plugin should be much faster now. I see speeds between 1.5 – 3 seconds on web inspector now.
The slowdown can be caused by image-resizing and caching as well. First time a new item is searched the image thumbnails are created, which takes a bit of time. The second time is fast, because the images are not re-created.
Also, WooCommerce did something to their core within updates 2.3.x, whereas every ajax powered plugin experiences major slowdowns in some cases. I have already contacted them, but no answer yet. Hopefully they aknowledge this issue, as it's affecting thousands of plugins.Best,
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