Newbie question:

I just stored my first purchase using mSigna wallet by connecting to a remote node. I had to enter a long sentence when I created a new wallet in mSigna. I have saved this sentence in a text file on my portable drive.

My question is if for some reason mSigna software stops working in the future, would I be able to access my bitcoins using a different wallet software as long as I have that sentence saved?

I played with mSigna little bit on my own and I see that it has options to export public and private keys to a file. Is the format of these exported files proprietary to mSigna?

Even though I don't have answers to the above questions, I have backed up the "keyphrase sentence" and the exported public and private key files to a portable drive. Would this be sufficient to be able to access my bitcoins from any wallets in the future? If not, what do I need to do to be able to do so?

Thanks