Here are my thoughts after running this in Silas Marsh:

• This has been a great horror soak replacement for Peter Sylvestre so I can run On Your Own (perm). I'd pay 4XP to upgrade to two Peter Sylvestre (2) if I wasn't playing On Your Own anyway, so that feels like a wash to me.
• Both versions of this work really well to keep damage and horror off of any of the Level 3 composures in this set, (Plucky (3) for Silas), but I think Plucky (1) from Echoes of the Past is the better combo; this version of Precious Memento "heals" horror from itself (on Standard difficulty Silas is easily passing almost all tests by 2+) and you don't have to worry about "healing" damage from it because Plucky (1) doesn't soak damage (so it can't force you to put damage on memento instead of it).
• While it usually won't be defeated by horror, it may still find its way into the discard pile (the previous reviewer also noted that it commits for just like Unexpected Courage), so Resourceful and Scavenging (and William Yorick!) get it back.

This is a rare Item, which Bob Jenkins already running Scavenging for other stuff can get back (with e.g. Lockpicks) when you feel like you already have enough damage sponge items to recurse. Instead repeatedly commit it like Unexpected Courage to make it quickly go to discard pile again rather than wearing it for soak risking having longer period you don't have it in hand to commit. A combo newcomers with just Revised Core and EotE can perform.