My favorite weekender right now is the Rogues Gallery tote featured above. It has a detachable section, which can serve as a dopp kit among other things. It looks to be good quality leather made to look worn and old. Hell, you could even lie and say that your Grandpa had it with him in the War, she might believe you. For $900, we certainly hope she is impressed by it and turns it into a conversation piece.
On the other end of that spectrum is the buffalo check Weekender from American Eagle. It probably won't hold up for centuries, like the Rogues Gallery bag, but it certainly has a cool look. Also, considering it is a modest $80 online, it certainly is quite a deal. One note, always go to stores to order online items, they will order it free at the stores and not charge you for the shipping.
This Bobby Jones bag is not going to win any prizes for... anything. It is not offensive looking, it will hold a lot of stuff and it is around $70. It is another solidly inexpensive option.
The Cutter & Buck leather bag is a bag that will only look better with age. It is high quality leather, simple, classic design with all the right straps and pockets. The leather will age with time giving it a nice patina that will make the bag look even better after years of wear. Good leather like wine always ages gracefully, hopefully your date will too.
The Weekender from Mulholland Brothers is quite durable and useful, it also looks like a house calling doctor's bag. The two-tone leather is a nice touch and one you'd expect on a bag that is selling for $145.