This site did not show evidence of storing passwords in plaintext.
This site does allow secured connections (https)
This site did show a clear way to unsubscribe from their emails
This site does verify your email address.
Below is a sample of the emails you can expect to receive when signed up to FlashFXP.
You are receiving this email because you just signed up for an account on flashfxp.com. (Or at least someone using your email address did.).
To finish activating the account, please click the link below to validate your email address.
If you did not request an account on our system, simply ignore this email, and the request will expire in 24 hours.
If you have trouble validating your email address or require further assistance, please contact us https://www.flashfxp.com/contact