Reasons in favor of the Blue Jean:
1) Blue Jean is sooooooo Hermes
2) Blue Jean is tremendously versatile, it practically matches ANY style and colour you wear. Plus, it's a summer/winter colour.
3) For me, Epsom is a great choice for the big Hermes bags because it's
light - we're talking about a 35 here, and with a heavier leather + hardware it's already a lot to carry, even when it's empty - imagine full!!! No wonder Jane Birkin got tenonditis! Spare yourself!
Reasons against the Blue Jean:
1) Easy to find/easier than Raisin (??) (I'm not sure I share that view)
2) Not liking Epsom leather (I don't share this view at all - Epsom is among my favorite ones - it's light, it's extra durable, it looks more refined than other "thicker looking" leathers and it shows the hermes colours exceptionally well)
Reasons in favor of the Raisin:
1) Magnificent colour, surprisingly very versatile as well
2) Does not get dirty
Reasons against the Raisin:
1) In my opinion, it's a very "winter-y" colour.
2) I don't like very much clemence in general
3) I don't like
at all clemence in big Hermes items - it makes them look bulky
My personal opinion favors keeping the Blue Jean Epsom.