Another IOTA cold storage question.

I'd like to get my IOTA tokens off the exchange somewhere secure and cold. I'm reading that some people are not using IOTA wallets right now and are actually keeping their funds on exchanges. No way this is the right move, right? I see there are some mobile wallets and I see a windows wallet available. I'm on a mac and can spin up a Windows VM if need be. Where can I generate an address/wallet seed that I can put in cold storage? I see that https://iota-wallet.org/ is displaying a message saying:

"The wallet is currently being reviewed on the IOTA testnet. Please move your funds to a different wallet in the meantime".

So should I not use this wallet to generate addresses right now?

Also, I read this: https://www.reddit.com/r/Iota/comments/6hkcbb/iota_how_would_i_do_cold_storage/dizelga/

Is this IOTA ADDRESS Checker/Generator legit and safe?