Everyone has his own strategy in mining and it is up to you to decide what type of contract fits you the most, we will provide you any info you need.
As this one:
- the 12-month contract gives you an opportunity to have more BTC mined faster due to no fees applied and the ability to withdraw any mined BTC amount at the end of the contract period, yet it works for you only for 12 months.
- the open-ended contract does not have an end date and is more applicable for people, who prefer a long-term opportunity to mine BTC, as it has a maintenance fee, that makes the BTC accumulation a bit slower, but not limited by any timeframes.