Ptaldorr, if you're committed to applying a preservative, the LAST Record Preservative seems to be least likely to do harm. But, my recommendation is to focus FIRST on excellent cleaning using one of the very effective record cleaning fluids such as Disc Doctor, Record Research Labs or Audio Intelligent. If you're not using one of these (or a couple of others), you're simply not hearing your records at their best even though you're using a very good rcm.
FWIW, I used a home brew cleaning fluid, a VPI HW-17 rcm and LAST preservative. Once I started using Disc Doctor Miracle Record Cleaning fluid and brushes (together with my rcm), I started getting consistently superior sonic results from my LPs, and I've stopped using the Last preservative. My philosopy with many many used and new records in my collection is now: clean very well before 1st play with Disc Doctor, use a carbon fiber brush before each play, handle and store correctly. I have no doubt that my collection will last beyond my lifetime.
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FWIW, I used a home brew cleaning fluid, a VPI HW-17 rcm and LAST preservative. Once I started using Disc Doctor Miracle Record Cleaning fluid and brushes (together with my rcm), I started getting consistently superior sonic results from my LPs, and I've stopped using the Last preservative. My philosopy with many many used and new records in my collection is now: clean very well before 1st play with Disc Doctor, use a carbon fiber brush before each play, handle and store correctly. I have no doubt that my collection will last beyond my lifetime.
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