Could you show us which bags you are looking at so we can tailor the advise to you?
If it is important to you to buy a bag and have it hold it's value, because you plan to use for 3 months to a year then sell, go with Tory Burch. I still see her bags in consignment shops for $150-200, which is not what you will see with Kate Spade.
That said, Tory Burch may not be practical. Hardware heavy bags by TB tend to get... well, heavy. My mom doesn't carry hers for that very reason.
Kate Spade leather bags are actually very high quality. I met my boyfriend at a pretzel plant, so my mom bought me a KS pretzel bag for Christmas last year. I carried it, no joke, for the better part of the year - and it looks brand new.
KS also gets great sales prices and has good deals at their outlets, too.
Good luck; I hope some of that generic info helps