Tbg, I have to say that after a couple hours of listening to my system using three LPIs each augmented by Mapleshades on the VAC chassis, I find I am substantially better off than without the Mapleshade weights. No downside so far. The upsides are: more body and color, better voice and instrument separation, better bass, less edge on vocals and even instruments, i.e., more rounded and natural. That is to say I am finding that the benefits of using the LPIs are magnified. Of course, without a doubt and in line with Whatthe suggested earlier, these benefits are possible primarily because of the very high quality circuits and parts of the VAC 160iSE. What I am assuming the SP LPIs do is eliminate chassis resonance, which probably leaks into the amp circuits and even perhaps the tubes. I am curious to hear what you didn't like with the extra weight of the Ultra 5s versus the LPIs, as I will keep a watch for that.
Thanks again.