It seems like they are very similar and sort of personal preference (they look really similar and both have one handed folds), BUT just from reading reviews from Hellobee and Amazon, these are my major concerns about both:
-Britax B Agile:
Cons: Reviews say the basket is smaller and less accessible (not that big of a deal). Most reviews mention that it does not sit up very straight, which makes it very uncomfortable once your child is older than a baby and wants to be able to sit up and see out. *many* reviews on Amazon mentioned this. Also, because of this, the child tray doesn't really work because the child is too far away from it to use it. Boo. (is there a pad or something you can buy and put behind the child when they are older, so they can sit up straight?)
pros: The travel system--big pro in my mind. The higher kick bar in the back.
-Citi Mini Jogger:
Cons: Need to buy a converter to put an infant car seat in it...so, added expense in the beginning stages. That's a big con to me.
pros: slightly more headroom. Some people say handling is better. Appears to sit up a little straighter for when the child is older.
Both: Everything else seems fairly equal. WHY can't they just make the Britax sit up a little straighter OR have a travel system for the Citi Mini jogger??? That would make my decision so much easier!!!!
I also found this thread on Amazon that compares the two---but is there anything else I should know? http://www.amazon.com/forum/baby/ref=cm_cd_pg_next?_encoding=UTF8&cdForum=FxSKWDWQRZ03WU&cdPage=2&cdThread=Tx2CO2B2V69N45G