The majority of cloud mining companies are nothing but scam, the rest are overpriced, Viabtc offers a legit cloud mining service, I have not tried it but I use viabtc for mining and they are indeed trusted so it's highly unlikely that such a large pool will turn out to be selling scam mining contracts.
I remember ViaBtc terminating all cloud mining contracts:
https://support.viabtc.com/hc/en-us/articles/4402753997721-Announcement-on-the-Termination-of-ViaBTC-cloud-mining-serviceWe are sorry to inform you that all cloud mining and offline mining operations on ViaBTC will be terminated due to the requirement of full withdrawal of cryptocurrency mining according to the policies in Mainland China.
As a result, all ViaBTC mining farms will cease operations and so will the cloud mining service. Meanwhile, the mining income allocation of the BTC36W2312 and ETH5W2312 cloud contracts will be terminated at 00:00:00 June 25, 2021 (UTC).
Seems like bitdeer is the only one left but with those prices, and the 1080 days plans, I can't picture myself sending in advance money for 3 years with the current situation, not even mentioning the plan starting "to mine" on the 31st of October.