Ever-tighter building regulations on energy efficiency continue to work in SIG's favour. The last introduction of new UK standards in 2006 prompted a 20 per cent rise in the volume of insulation materials per building in the following three years and there is no reason to believe that their successor, which comes into force in September, will be any different. At 128½p, or 18 times current-year forecasts, buy on weakness, says the Times.Greggs shares, which trade on a 2010 price to earnings ratio of 13, are bang in line with the average for the retail sector. But the Independent thinks 2011 may be a better time to start tucking into its shares. So for now, hold.Fenner's most important trading period ? the three months from March to May ? still lies ahead. But, at 188p, or 12 times current-year earnings, those who followed the Time's "buy" advice last April at 80p have every reason to hold on for more.Mears is either a buy for safety, or one to avoid because there are better returns available elsewhere. While the Independent likes the company, and think it is a good long-term bet, the shares have underperformed the market since it last looked, so it still say avoid.The longer-term case for Ashmore remains. With emerging markets' contribution to world GDP forecast to rise to 50 per cent before the end of the decade, the allocation of institutional cash towards their debt should increase steadily. Ashmore's 18-year track record within this niche, operating margins of nearly 70 per cent and the £300 million of cash on its balance sheet only add to the attraction. At 245½p, or 15 times earnings and yielding 4.9 per cent, hold, says the Times.Please note: Digital Look provides a round-up of news, tips and information that is impacting share prices and the market. Digital Look cannot take any responsibility for information provided by third parties. This is for your general information only as not intended to be relied upon by users in making an investment decision or any other decision. Please obtain a copy of the relevant publication and carry out your own research before considering acting on any of this information.