I received 4 free buttshakers when I purchased 4 chairs from 4seating. I have read some reviews and the consensus seems to be that they are worth putting in. Here is my dilemma ... I am significantly over budget on my home theater and I am looking for a way to save any money at all. The 4seating site has the lowest end amplifier selling for $299 and they go up to $599. Three questions: 1. Are these amplifiers specific to "buttshakers" or are they just amplifiers? 2. Is the tactile feel going to be significantly different by upgrading an amplifier from $299 to $599? 3. Can I get a cheaper amplifier that will accomplish the same thing as the $299 amplifier? Any help would be greatly appreciated ... I am SOOOOO over budget but would love to add this finishing touch to the project!