This has been climbing for a couple years now, and they've got serious steam. Foils are good buys around $4 right now, expect them to double by next Spring, if not sooner. Mystic Speculation is your sure-fire data-driven bet.
I really like this card in combination with Memory Crystal. If buyback ever gets a revival, you can bet a $0.30 Memory Crystal will jump to $5.00 in a hurry. Memory Crystal is a low-risk, high-unlikely reward, one of my favorite types of long-term holds. Notice there is no minimum buyback cost of 1, so Mystic Speculation gets a free buyback.
Once a low-print uncommon hits $1.00 with momentum, it has a high likelihood to continue to $2.50-$3.00 within short order (Terminate, Condescend...). It just the nature of the proportional growth that happens in this price-range. This is my favorite price range to speculate in, because the percentage profit can be great (2x to 4x returns in one year), they're below the radar of most speculators so are rarely if ever a bubble (i.e., they are usually casual demand), and flat-rate shipping costs cause many vendors to build the value of these items into their shipping costs, which is divided among many cards if you "buy them out".
Buy Mystic Speculation non-foils at or below $1.00 (the better bet right now, short-mid), buy Foils at or below $4.00 (mid-long).