Yes. Does your client have a HD symbol on the lower right? If so, then it would definitely be good to just have it backedup once.
Well... it does have "HD" but it has a line through it. I didn't think it had the line through it, though.
If it has a line through it, then it is NOT using HD, and it must have been created with an older version of the software. However, if you back it up then, it should still be alright. Just don't continue to send money to the backed-up wallet.