How do you prefer to wear your bag? Actually, these 2 choices are very different.
Chanel jumbo - wear on the shoulder or cross body. Can't hold too much. Very expensive. I'd suggest you to get one in cavier since it's more durable. A classic.
Celine luggage - handheld or wear on the shoulder if you are slim. Hold tons. Not cheap, but half the price of the jumbo. I'd suggest you to get the pebble type since it's harder to get scratches. Not yet a classic and I personally don't know how to classify it yet.
Do you carry a lot? Do you want your hands free? Can you afford it comfortably? What's your life style? How do you usually dress? Seriously, if you reserve a Boy for special occasion, I don't think a jumbo is a good choice for you. But the price of classic also climb up too fast. You may want to consider that.
If take the fact that you have a Boy and reserve it for special occasion, I'd choose Celine mini luggage, but I'd prefer a solid color one. Or if you really want a Chanel, try visiting a boutique or browse the forum and their website to see style you may like.