Pros
You get to see the product road map up to 6-8 years out and it can be fun playing with new technology. You get to make awesome designs for great people. You will learn a lot. Take advantage of their school reimbursement programs and any skill programs offered. It will be the highest design standards you will work with in your career. Material, tolerances and finishes must be perfect. Max our your stock options and when vested 401k. You will learn cutting edge design methods and have excellent standards and practices. Overtime is good, this can even go to double time in some cases. Having an extra 2-4 hours of overtime a day adds up. Just make sure to pace yourself and take care of your health. There is always something to do. If you love the brand it will draw you in and you will have a role in bringing Apple's products to life. Your work will have an impact on millions of people. You will do the work of a higher paid position so it will be nice to get that experience. If you are doing good use this to get a higher position elsewhere, it will help you advance your career faster.
Cons
Management tends to be very self centered, not as much focused on growing your career but in growing their own. This can often cause tension as lots of people are vying for attention of higher ups. Expect to do all manner to tasks to help the team and your manager. Some will be menial but they will lead to more fun and complex projects over time. Make sure you do all your basic work before seeking to get to advanced work. There is not a lot of ownership of responsibility in management. Often they will kick downward. For example if they made a call on a design direction and it turns out that the higher ups do not like it they will blame the worker following their request in my experience. Do not count on accountability, however I would recommend if your manager is rude or does something out of line let Apple HR know immediately. It will save you a lot of hassle down the line. Politics is huge at Apple. Pay very close attention. People will pretend to be your friend or interested in your work to make a connection. If you get too popular with higher ups in a different team management can punish you, even if you were doing your job. Have a pulse on politics. Rank is big at Apple. Apple's biggest flaw is they rush themselves to the breaking point where for no reason. Often cutting already tight timelines for small reasons rather than give someone an additional 8 hours to refine a design. They can set the deadlines and standards but they often push people far beyond reasonable limits and in some cases the deadlines can be changed just as easily as they are set. In some cases I have worked 28 hours straight on a prototype that could just have easily been move out one day. This creates a scramble culture where you will be under a lot of stress often. You will be blamed for not doing work fast enough when often you can be given timelines that are not physically possible. In those cases be prepared to set expectations so you will not be taken advantage of. The average day is 12 hours. During a build it typically goes until the project is done. This mind you will get you a 'meets expectations' on your review. Doing above average work is average for Apple standards. You need to go above even that or have a good political connection for the next level. Often you will have to leave the company/position you are in to get a promotion of any value. Its such a waste that Apple does not help grow people's careers especially after investing so much time into them. You will often be asked to do the work of others and get no credit for it, even if you do your own expiration be careful as your manager may take your idea. Document everything you do, this will help. You will often be pushed to commit everything to work and be accessed at all hours of the day. Be careful in how you set boundaries as this can often lead to you not being seen as serious. You will often do the work at a higher level than your current position but not be paid more for it. You will often help people make extremely complicated projects and get no real recognition for it.