In recent times, I haven't really bothered covering non-Angus Reid subsamples from GB-wide polls of Westminster voting intention. However, this one is interesting, because traditionally Ipsos-Mori (like ICM) haven't troubled themselves with Scottish subsamples at all, instead lumping Scotland into a "northern region". The sample size is so small that the figures have to be taken with a lorry-load of salt, of course, but for what it's worth they show the SNP in the lead -
Liberal Democrats 6%
Those are the figures for all "certain to vote". Among all respondents, the SNP lead by 39% to 31%.