Is Muraqaba allowed for Sunni muslims?

I've heard arguments from different people saying that it isn't. And well I wasn't really sure about it either since I saw that in some cases they said you have to visualize the face of a Shaykh and use that to go through the three different levels eventually getting to the point where you can achieve a oneness with Allah. Tawheed or as the final stage is called Fana Fillah. Now I like the idea of it but I'm not sure about using a Shaykh to acheive it. Shouldn't it be possible to do that without using the help of someone else? I did find some websites saying that you can achieve it without doing that but they don't really say how.

Similarly I was wondering what the stance is on Astral Projection and using the Basirah (inner eye of the heart) and if anyone knows any websites where I can find some steps to follow to be able to use it.

Thanks