I liked thisvideo from TechCashHouse.
My understanding
- It can still be profitable to mine if your electricity is cheap and the bitcoin price don't drop too much in the next 6 months
- Bitminers electricity cost is important
- You may require a dedicated room because of the noise
- It will generate a lot of heat, which can be an issue in a hot climate
- Pools are required to get reward due to bitcoin difficulty, they will grab 1% of your profits (ex: Slush)
- Difficulty and Reward rate has to be considered
- Antminer S9 is one of the best for mining bitcoin
Information I gathered elsewhere
- If you want to make a lot of mining, you will probably need to start a business, put expenses and profits in a specific bank account and have tax to pay in mind
- ASIC miners are specialized for bitcoins, but can't mine some currencies like ETH
- Specialized video cards are required for ETH and other crypto currencies
- Videocard may start to get harder and harder to get due to some manufacturer stopping doing it recently
- Purchasing from bitmain directly may be safer and cheaper, but you may have to wait 6 months to receive it, as some order from last year in october aren't sent yet.