The sights are completely different designs, but the tritium (gas that makes the glow) is the same and has the same half life so you will get the same performance out of both of them. I would get your hands on them and see which sight picture works best for you and then pick that one.
Heine sights are "straight eight" one dot on top of the other. see pic http://www.heinie.com/images/bigsprgfldXD.jpg
trijicon are 3 dot sights. see pic http://www.pistolgear.com/prodimages/trijicon_lg.jpg
straight eights are nice once you get the hang of shooting it, but the traditional 3 dot is more universal and more natural. B
Heine sights are "straight eight" one dot on top of the other. see pic http://www.heinie.com/images/bigsprgfldXD.jpg
trijicon are 3 dot sights. see pic http://www.pistolgear.com/prodimages/trijicon_lg.jpg
straight eights are nice once you get the hang of shooting it, but the traditional 3 dot is more universal and more natural. B