I have a Syrian hamster - she's a great pet for a working adult like me, but bear in mind when they say nocturnal they mean often not awake until 8/9pm at night, like ours. If you wake them up, not only is it not great from a welfare perspective but they tend to be grumpy and that's when they're more likely to bite. I love my Syrian, but they're not good pets for young children due to being nocturnal.
With regards to cages, they need to be at least 80x50cm unbroken floorspace (shelves are bonuses, not replacements, for floorspace). www.woodgreen.org.uk/pet_advice/557_hamster_accommodation The bigger the better - my Syrian is in a 100x50cm cage. Yes, this is bigger than some rabbit hutches, but it's what they need. Zooplus.co.uk does some great cages - look at the Alaska / Barney / Alexander models. You also must have a wheel that is at least 28cm diameter - anything smaller, and they will have to bend their back to run and that causes painful spinal problems.
My Syrian is a demanding thing - incredibly sweet, but she will let you know when something isn't to her liking, or when she's bored! In some ways she's easy to look after, but in other ways she's still plenty of work - she needs at least an hour of playtime outside her cage daily. The two Syrians that you plan to get must never come into contact with each other - they'll either fight to the death or (if opposite sex, and the female is in heat) mate.
I have a dwarf too - don't think that they're better options because they're not. Dwarves need cages that are just as large, are faster and more prone to biting. Pairs of dwarves often fight and need to be separated permanently and immediately to avoid them fighting to the death.
Good info here on suitable and unsuitable hamster mixes hamsterhideout.com/forum/topic/102520-hamster-nutrition-iv-commercial-hamster-food-list/
Bedding - there's a wide range of options out there. I favour Fitch www.fitchrecycling.co.uk but Carefresh, Auboise and Megazorb are also commonly used. They need to have at least 3-4" deep to dig in. Avoid any "fluffy" bedding that resembles cotton wool - it's incredibly dangerous and can cause anything from fatal gut blockages to amputations.
Syrian hamsters can be wonderful pets, but I'm afraid they're not the easy children's pets that people often mistake them for.