I have one of the aphex exciters with the "big bottom" that I bought after reading a strong review. the purpose was to be for the additiona of bottom end in certain types of music, some sort of expansion. In any event, I rarely use the device. Ultimately, I just don't like adding it into the signal chain because the benefit does not outweigh the burden. I going to try using it for helping to fill out string lines and see if that is a good use for the device. Ultimately, and this is the most important point, a great EQ is a better bet. More versatile, more control.
By the way, when I purchased this particular thing, I was fairly new to the recording scene, in about three months. To figure out what to purchase, I did allot of reading. I did not catch onto the extent of the potential bias factors of the reviewers.
On e last thing, I recently did one of my best recordings and mixes ever and so far have not used the box in that particular mix.