Please try and find out if they replaced all 4 elements, or the whole seat cushion - if it's all 4 elements then part numers etc would be ideal.
Both dealers I have contacted say that I need a new seat cushion - I prefer the current setup over the one I described above - the one above does not warm the side bolsters.
If it's a choice of $400+ for a new cushion or a cold @$$ - I'll take the cold @$$!!!