The main thing that consistently comes up in feedback on the "big boy" PC's is added low frequency information (bass). When you finally audition a PC in your system that has this, you will then be able to decide whether it is worth the money to you. I get this from the BMI Whale Elite PC's that I use on my player and DAC. In this case the additional bass information (stuff that was just not there with the other PC's that I had tried) is coming from the source itself and not the amp alone (which is running a $50 Absolute PC). This, again is something that really needs to be heard to be believed. The BMI's are the least expensive PC's available, that I am aware of, that offer this improvement. They also sound better to me in all the other areas that we harp on, but again the main thing (the real shocker) is the bass that really separates them from the other PC's that I have used in the past. I was originally going to start with just one, but happened to sell a painting on Ebay at the time of the purchase that covered the cost of two of the PC's, so lucked out in this respect. The highest retail on the PC's that I had tried before was $280 and the others ranged in the $150-$200 price range. Anyway the BMI's at under $900 for the pair were worth it to me, but I doubt that I will go any higher other than an audition and a Beta test of a few more PC's (higher retails) that I have scheduled for later this summer. I will just have to see how the auditions go and perhaps I will change my mind. If one has the budget though, I don't see a problem with diminishing returns as long as there is an improvement that makes you happy. I assume that your PC's were at least $100 each which is beyond the cost level of diminishing returns that others in this hobby have established for themselves. It's all relative. The hard thing for me to do is to be happy with the improvements that I do make, as the exhilaration from them soon wears off and then I always want more. I have to remind myself from time to time, to just sit back and enjoy what I have accomplished to date. I am getting better at this though and am therefore happier with my system and am enjoying the music as it should be enjoyed (without thinking of the gear).