EMI versus Seraphim recordings

Hello. I'm wondering if there is any sonic difference between EMI and Seraphim recordings? I seem to recall that Seraphim is the discounted reissue label for EMI so perhaps this makes a difference. Specifically, I am looking to purchase the record set of the Symphonies of Carl Nielsen with Herbert Blomstedt and the Danish Radio Symphony Orchestra which is on both labels. If there's no sonic difference, my preference is to get the Seraphim set as it contains his overtures, which I would rather have than his concertos which are on the EMI set.
Thanks