I can't find the Navi SP/DS chips... also MMBN 5 DS and Boktai 2... they any good?

I havebeen searching and I ahve heard so many stupid stories on how to gte them its impossable for e to figure it out, I need to find basically my whole teams DS/SP chips and I can't, also Gridman, larkman, and cosmomans DS chip. then to go with this i was wondeirng what some suggested Navi Custs are or folders for fighting these navis.

Then i was thinking about purchasing Boktai 2 and Megaman Battle network 5 DS: Double team for my DS, but I am currrently curious if any of the two are worth the money or if they are as good as ppl make em sound?