The hours suck. The bigger the company, the more it suck. Banks do their promotion of application, system, network to live from 2 to 3 am or later. There are systems that are even more heavily used than banking systems, eg transport and shipping systems. These changes are done on Christmas and New Year. So you can kiss November and December holidays goodbye.
A large portion of IT employers expect you to know your stuff and certified eg MCSE, MCSA, CCNA etc. There is very little upgrading provided. Any training is likely very niche and targeted. So you will need to do a lot of self study and face time with a virtualization software.
Due to the continuous interaction with many different systems and requiremens, pace of learning can very different. In 6 months, what you learn at a systems integrator job is more than 3 years at a end user sysadmin.
After going throuhgh all the above, you will be certified in in a few areas. The vendors roll out new version of their products every 2 or 3 years, the related certification needs to updated and renewed. For systems and applications, sometimes you can use virtualization to test drive during lull time aka at home. No so such luck for network engineers, as they need the physical boxes.
So for all these what do you get? The ability to change the productivity of the users and if you are at an online shop, the bottom line.
Lastly, here is something for you to think about:
For males, there is a more than a good chance you wife is an accountant.
PS: Do you know it is really difficult to hire a male Chinese Singaporean Citizen Network Engineer?