When I began, Dash was easier to reach the minimum withdrawal value, and was worth more STEEM. I've just checked, and it seems that Litecoin may be a bit easier now that its price has dropped a lot (so we need less of other cryptos to convert to Litecoin). But I did a simulation, and Dash seems to still be giving a bit more STEEM.
As I write this, 0.002 Dash (the minimum withdrawal value) is trading for 0.867 STEEM on BlockTrades. If converted to Litecoin at CoinPot, 0.002 Dash would become 0.00222500 LTC, and trade for 0.858 STEEM on BlockTrades.