Good advice.
Using an alternate cryptocurrency client would be a great way to get many people to install a hidden virus that targets Bitcoin users.
If you have a significant amount of Bitcoins, I wouldn't run other clients on the same computer until the alternates have developed trust over a longer period of time... I'm probably on the paranoid side of things though.
These new cryptocurrencies are interesting, and it will be fascinating to see how it will all play out.
You should be safe in every investment you do. Thisis a very risky place and all actions we do always have to be counted and checked many times!