The Bleach flashbacks are better then the Naruto one's. Like Bleach it's better and we don't know a lot about it. Naruto is all the same. What do you think?
Naruto - they are not the same, different people add to the story from their point of view. Plus, Naruto flashbacks help a lot in it's Timeline, cuz unlike Bleach, Naruto has much, much, much more complicated Timeline.
Bleach doesn't do it as often as Naruto does, and the flashbacks aren't as essential to the story either. We see Madara's flashback to understand how he met Hashi and how the hatred started that fuels the whole plot of naruto now.....
in bleach we see Ichigo's Mom's flashback because apparently she's a quincy, making Ichigo a half quincy, and the enemies are quincy....
Bleach have more flash backs that give you valuable information, I started to hate naruto flash backs when they started to use obito getting friend zone as a freaking excuse to start a dang war, felt like a waste of a chapter cept for the part where kakashi kills rin and obito unleashes the most demented jutsu ever.