If people are still mining it, it ain't dead.
I mine sloth regularly, and trade it
Biggest prob with old coins is 1) Finding wallet, 2) syncing wallet, 3) finding a live exchange, also most exchanges that had it already de-listed it years ago, and really dont want to have it back.
Best thing to do with old coins is to mine them really really gently, never with more than 30-35% of total network hash (or u either kill it, or are just competing against yourself and the block time), and do it real discrete, slowly let it gain some traction, problem is, if an idiot jumps in, hits it with 10-100 x total hash, which is easily done with asics etc, then it forks all over the place, then exchanges will never touch it, and we lose another great old coin. I mine some coins at less than 4kh/s on scrypt, and 250kh/s x11....take a mo and look at those figures, and i'm getting coins along with the other miners all day. This way i can be mining 20-30 old coins all day every day, on a couple of old gpus. I mined 1 mil of 1 old coin in 3 weeks, never getting above intensity of 10 (8-25) and hash around 1Mh, x11
So, steady away, and have fun, and if ure lucky u'll mine 1000's of coins and hopefully they will be worth something oneday
*old skool*
J