in my opinion cloud mining is not really a scam if they really have proof of mining equipment to support their project. but you need to ask yourself why they will sell their equipment if they earn from it. i try to invest in cloud mining before and the good thing is until now i still earn  from it but the earning is super low if you will compare it in the real earning of equipment you bought. if i will convert the coin i use to purchase the equipment i will have better profit right now.