I am gathering gene expression datasets, what i want to know is that will datasets got from SMD be of higher quality than those got from GEO? I know that GEO is large and there are no quality checking procedure when people submmit data to it.
I do not know that such a comparison has been done, but the data in SMD are largely mirrored to either NCBI GEO or ArrayExpress. More importantly, the number of samples in SMD is tiny compared to those two larger databases. In general, for microarray data from a public repository, it is a REALLY good idea to do some QC before serious use.