Well, in your country you don't have much of a choice when it comes to dwarfs. You have Hybrids or Roborovski. Depending on where you live you may have the choice of Pure Campbell Hamsters if you can get to the only Hamstery in the USA that has pure Campbell. I'm not 100% sure on winter White but I know no Pet Store has pure ones.
But here are the pros and cons in my opinion:
Roborovski
Small cute, Sandy Coloured (occasionally white) Hamsters. The smallest of all our pet Hamsters. Very active, Very quick, not generally suitable for Small Children or those that struggle with fast moving objects. (Aka, me, not suitable for me because of Epilepsy xD)
Pros :-
- Cute
- Entertaining
- Little Eyebrows
- Not prone to Diabetes like Hybrids, Campbell and Winter White.
- More likely to run away than bite during taming.
Cons :-
- Fast
- Can have neurological issues such as excessive digging, pacing back and forth, etc.
- Can be harder to tame than Hybrids, Campbells or Winter Whites but it isn't impossible.
Hybrids
Hybrids are the result of crossing Winter Whites with Campbells. These are the ones you find in Pet Stores labelled "Russian", "Campbell" and "Winter White". Not recommended to breed them because of the fact that the babies can be too Small for mum sometimes, also because of the huge risk in Diabetes and Neurological issues.
Pros :-
- Much easier to obtain in the USA than Campbell and Winter Whites.
- They come in a Lovely Orange colour (sometimes called Mandarin)
- Somewhat easy to tame.
Cons :-
- Very prone to Diabetes.
- Very prone to Neurological issues such as Star Gazing.
Campbell Dwarf Hamster
Campbell are cute chubby hamsters and are the most commonly know out of both WW and Campbell hamsters. Like Hybrids they can be prone to Diabetes. Very rare in the USA, however some people in the USA are hoping to band together and increase their numbers, at the present time only 1 Hamstery breeds pure Campbell Hamsters.
Pros :-
- Very sweet usually.
- Very chubby looking
- Come in some interesting colour and patterns.
Cons :-
- Can be prone to Diabetes.
- Can, from certain lines, be Cage Aggressive.
- Rare to find in the USA with only one Hamstery breeding them at the moment.
Winter White
Similar to the Campbell, unlike the Campbell the WW is meant to be an Egg Shape. Hard to find in the USA.
Pros :-
- Chubby appearance
- They can change coat colour.
- Can be very friendly.
Cons :-
- Hard to find in the USA.
- Their nails grow a Million Miles an Hour.
I don't personally see Chinese Hamsters as dwarf hamsters because Chinese Hamster belong to Cricetulus and Dwarf Hamsters tend to be in Phodopus, but here are the Pros and Cons of Chineseys anyways!
Pros :-
- Cute tail
- Kind of shy but not too shy.
- They always look cute.
- Pancakey shape.
- They like to Cling.
Cons :-
- Prone to Diabetes.