Use @Html.Raw() with caution as you may cause more trouble with encoding and security. I understand the use case as I had to do this myself, but carefully... Just avoid allowing all text through. For example only preserve/convert specific character sequences and always encode the rest:
@Html.Raw(Html.Encode(myString).Replace("\n", "<br/>"))
Then you have peace of mind that you haven't created a potential security hole and any special/foreign characters are displayed correctly in all browsers.