Is the Last Record Preservative system a worthwhile investment?

My experience with Last initially was not good. I found it really deadened the sound, the dynamics of the recordings. It seemed to make them a lot darker. I was cleaning the older records I had purchased more recently and that had surface noise. I used the GEM Dandy record cleaner and then followed with ultrasonic bath and then Groove Lube, which must be used very sparingly and according to instructions. Then, at the end, I applied the Last. I found the initial results quite disappointing to say the least. The records were, however, much quieter and the surface noise was pretty much gone. The Groove Lube left a bit of gunk on the stylus but I removed that easily enough on each side with the Magic Sponge that's been recommended here many times for stylus cleaning. I got busy and then came back a few weeks later and listened to other LPs I had cleaned with this method. Well, after waiting several weeks, the Last preservative was no longer imparting any kind of unwanted sonic effects. The sound had changed completely back to normal. I still have not applied it to the brand new records I've purchased, but I will say that I will continue to use it for older LPs and I might try it on new ones after I've had more experience with it. So I would recommend it then so long as one gives it enough time to fully settle in.

@blueranger , I am curious why you only use Gruv Glide on your most worn records? I was/am a big fan of Sound Guard back in the day. The LPs I treated are still new looking and sounding. I was hoping Gruv Glide was a vert similar product.

As for my experience with LAST, I used it foe a bout a year after each LP I cleaned. I examined my stylus under a microscope after playing a few LPs and saw no residue. I did hear subtle improvement in sound and noise. Nothing earth shattering; but as has been said it's intended to be a preservative more than a sound enhancer. So time will tell.

The reason I've stopped using it is because I now clean my LPs with a formula with Turgitol, similar to that used by the Library of Congress. That formula is said to leave a molecular layer that reduces static (and friction?) on the vinyl surface. It improves sound quality noticeably and seems to be lasting (no pun intended) quite well, so far - I only started using it at the end of 2016.

The reason I don't continue using LAST is that I don't know how it will react with my home brew. Which would I apply first? So if anyone has any experience, ....

rodman99999 - I second the motion!

Don't worry about it.   You should get bomb with a 1000 ideas.   Stick with what your are doing 
Forget about it. You will end up in a hospital tied
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