All our pellets comply with the strict ENplus A1 standard. Balcas Brites and Sparklets Premium have attained BSL approval while Gvijus have yet to gain this approval. Test results show that both Gvijus and Sparklets Premium pellets will generate slightly more heat per kilogram than Balcas Brites (due largely to the slightly higher moisture content of Balcas pellets).Ash & fines are very similar for all three brands. Although Balcas appear to have resolved the issue they had with long pellets we have found Gvijus to be more consistent than Balcas in this respect. We haven’t supplied enough Sparklets to be able to comment on pellet quality as yet although comments from other sites are positive.