<strong>PREMIER FOODS</strong><br />Warren Ackerman has upgraded its estimates in Premier Foods to &ldquo;buy&rdquo;. The broker sees positive returns on investments from its Hovis brand due to its 2008 re-launch. It says the company&rsquo;s balance sheet is no longer a cause of major concern, with attractive earnings estimates and a subsequent target price increase.<br /><br /><strong>SWISS RE</strong><br />Collins Stewart has recommended Swiss Re shares as &ldquo;buy&rdquo;. Improvement in solvency buffers due to fewer risky assets, higher interest rates and spread tightening are seen as encouraging by the broker. But Collins Stewart is still wary that earnings outlooks seem uncertain, reflected in a 14 per cent discount in earnings per share.<br /><br /><strong>ROLLS-ROYCE</strong><br />Charles Stanley retains its &ldquo;accumulate&rdquo; rating on Rolls Royce. The broker says an air of caution is warranted due to ongoing challenging conditions in the airline industry. Despite this, it sees the engine maker as better placed than its peers for a number of reasons, including their engines&rsquo; compatibility with young fuel-efficient fleets.