Discogs versus 45cat

Personally I find both sites to be great. Discogs to me overall has greater strength for getting participants of a song complete and correct. 45cat to me is a bit better for the album art. I also like how all the variations of a 45 release under a particular catalogue number show in one place in 45cat.

I have noticed that both sites frequently differ as to which song is in fact the "A" side of a particular 45 rpm release. The record companies themselves are often somewhat ambiguous with this.

Would anybody care to share their trick for quickly ascertaining which site is truly correct?

Is there any possibility of adding 45cat to the possible tag sources, Florian?

Thanks so much.