It is ok as long as couple practicing same are mature enough to handle such a relationship.Live in relationship is not to be taken as a license to freak and flirt around.It is basically an opportunity to know each other better.
In Indian scenario, the male gets a lot of relief from legal angle when in live-in relation.
Again in Indian context the female is at risk if her partner is inclined to take advantage of the live-in relationship.
The choice is entirely personal.A successful live in relation can be termed as an Ideal Marraige.