shit , cryptopia added coin and price halved ., it was better when was only in coinsmarkets
With current difficulty (3000) at 500 satoshi mining SIGT gives about 4$ per 1070 card with ccminer 2.2.
1/4 of blocks with 2500 coins reward are mined already. Mining reward will be halfed in ~12 days.
There are other more profitable coins. And it shows that 500 satoshi price is near bottom.
So, yes, it is good time to buy. Or do not sell at least.