interesting Q... to be worth something interesting in a few years, a then-vintage car will have to be available in way lesser numbers than those desiring it then (offer and demand). Problem is, the market is flooded with RTR stuff these days and doesn't command the "wow" appeal it had when we were kids in the 80's... it's affordable, it isn't novelty, there's one new brand a month and many many chinese clones, and people buying cars in 2012 will very likely not even remember it in 2013 already!!! So much for the most of the RC purchasers ATM...
what we're left with as people driving the market in 2030 are discerning enthusiasts that will focus on the oddball stuff... I think the JQ is indeed a good candidate! Danny's take on the 414 is great, but there's a trick, it certainly isn't available as nib in 2012, at least not at reasonable prices as it is already very collectible! the 934RSR Re-re is a good example too. For the others, and reviewing brands on by one, here's my arrogant analysis
-AE: none... The race stuff is standardized and fantastically soul-less even though it rules the track! The rest is plastastic small scale stuff... Maybe the later versions of the MTA4, those with the US flag body?
-Kyosho: MP9 TKi3 maybe, or the latest of the MP9's, if they had released a "WC" version after Cody King's victory now that would have made my shortlist! I've lost track of the on-road 8th stuff, but the last WC winning Fantom (or whatever the car is called) could make it too
-Tamiya: nothing... too many products and releases, uninteresting later stuff that is all TT01-based with only the bodies changing from one kit ref to another. Maybe the TRF'ed Durga, maybe the 501, but not even sure.
-Losi: The 22 is quite a breakthrough, and most of those bought have been ran... I think a bNIB 22 will command reasonable prices in 20yrs
-HPI: I'd say the 1st-gen savage was quite a stir in the market... I doubt it can be found in Nib any more. D8 is a love/hate thing, maybe the Hara version will be collectible. D4 WE could make the shortlist too.
-Traxxas: 1st gen T-maxx will likely be sought after as it revolutionized the market 13 yrs ago! Unavailable already. The later stuff will be worth nada, except the 5th scale thing, but then again because of the high starting price the multiplier will be lower!
-Xray: nothing. too confidential, no international wins. Shame though, their stuff is the nicest I've seen!
-Mugen: interestingly, Mugen gear has NEVER been sought after... That's because most of their products are almost perfect out of the box and hence lack a bit of personality, it's all non-nonsense stuff and flies below the radar altjhough it keeps reaping all kinds of titles. I have a nib Sting and I suspect it's worth $200 at best
In other words - don't keep anything boxed for your retirement savings, it won't pay off
Paul
it's easy to guess that stuff that was out a few years ago and already fetching crazy prices won't go down!