I've never tapped a birch nor drunk birch juice as its called, though its a common practice in parts of Eastern Europe. I'd have one reservation; Birch trees are very good at absorbing pollutants from the air which, whilst that's useful for humans living nearby, might mean the sap itself contains pollutants, so living in London as I do, not sure I'd risk it. If you live somewhere with clear, clean air (Scotland, Cumbria) or you know the air's pretty good where you are, then its probably less of an issue.

Love to know what it tastes like...

That's exactly what maple syrup is though not all maples are equal in terms of syrup. Sugar Maple is the one to use. The sap is then pasteurize before consumption.

Thanks for the reply’s I will have a go but only have a tidgy sip just to be safe.

Be careful to block the hole up afterwards. Birch trees have been known to 'bleed' to death after damage.

I've heard its good for making home made wine from as well.

Thanks again for the reply’s.