I am thinking about using Primsleur to learn Greek?

[Airpole.]

If your purpose in learning Greek is only what you have stated in your remark then I strongly suggest to you to forget it.

To reach the level of writing something correctly in Greek takes a lot of reading and learning and you will soon be discouraged to continue learning.

One of the resident answerers here, who according to his statements has been studying Greek for a very long time, is still far from writing something correctly, mostly because he can't stop thinking phrases in his mother language and trying to translate them to Greek, instead of thinking as a Greek.

So, if you seriously contemplate learning Greek it will for more than simply writing something on their facebook accounts. You can equally do that using your native tongue.