Not quite the investment, but at least a "decent" store of value. I'm thinking it's relatively also easy to move over time.
Just get one, enjoy it for what it is and assess from there.
Personally, I think there's a long term upside to it. Maybe not Sotheby's upside but I find that really good watches are able to hold their own over a 15 year period. What's going for the RM versus the other 2 is that it's relatively overlooked and there's not much RM variants that got re-issued that actually looks like the trilogy version. For example, the current catalog RM does not look anywhere near the trilogy version. If I can sell a regular version Speedmaster from 2004 for double the price (and God knows how many speedies are out there). A caveat though, pieces like this will probably go through a long period of value drought before it starts to pick up. So you're not looking at something that's going to STEADILY rise in value.
The only thing that could probably jeopardize its future is if Omega releases a manual wind version for it's 120th year. I'll be a 110 by then so if I'm lucky .. hahaha!
Seriously, if this aesthetic appeals to you, you'd be hardpressed to look for a better watch at this level of quality, historical importance (ok, the auto movement kinda dampens it but still) and I hate to say it as I bought new.. value.
If Omega can offer a recall so that they can retrofit the 60th with a manual from that Tresor.. crazy me will probably pay extra. That's how good it is.
Lastly, the RM 60th is for those who "get it". And i don't mean that in a snobby way. Fauxtina polarizes. The auto movement is a downer. It's probably the most boring looking of the 3. But for those who've been into the RM for a long time, this was as close as it was going to get dial-side / feel-wise to the original and while they could have done better, it's miles better than the previous attempts at using the RM logo.
Now, for you to actually post this question.. it's probably calling out to you