Hashflare is paying the best but reliability is also a good indicator. Both genesis and hashflare have both been experiencing issues with their service. However, Hashflare pays a significantly larger amount

How impressive was that recent Monero gain! All because of news that Koreans will be able to trade it

For Bitcoin mining on both of the websites, it's a permanent contract. The one yr vs 2 yr contracts are the ETH, dash and scrypt contracts which I didn't cover in this. Hashflare has always been good with