Be careful of the Purse Forum slippery slope. Many here joke about it, but it is real - you end up buying bag after bag after bag, spending more than you can and should, because you see all these bags being revealed that you never knew about, and there are so many "enablers" telling you to get both because you "deserve it" and it looks fabulous on you, and your SA is now giving you heads up on pre-orders or pre-sales, etc. You have been warned.
Now I'm not saying you shouldn't get the bag. If you have the money and you're being responsible, why not? But here are a few tips to avoid the slope.
1. Make a list of the bags you want ( hopefully it won't be a long list) in the order of how much you are aching to have them.
2. If there is a specific designer bag you want, buy that bag and only that bag. Do not compromise with similar bags from other designers, copies, knock-offs, etc! Compromising is unfulfilling and you will end up spending more in the process.
3. If you have several bags on the top of your list, buy the classic that keep going up in price first. If it turns out not to work for you, you can resell and recoup a big part of the cost.
4. Speaking of "not working out", research, research, research. The brands you list are very expensive and bad purchases could be costly so you want to make sure the bag/shoes looks good on you/fits, that it functions as you expect, and that you can wear it when you want.
5. Similar to my last point in #4, use your bag. There are soooooo many people here who post about not wearing their bags because they're a) too expensive b) too delicate c) don't suit their lifestyle d) get snarky comments from coworkers/friends/relatives. If you're going to be like that, then don't buy the bag because it would just take up your money, closet space, and make you feel bad in the process.
6. Finally, be self-aware. Don't get swept up in the hoopla. Buy the bag you want because you want it - not because of some external pressure or the internal pressure of your fantasy life.