fluffy bedding is the worst bedding to give them, im not too sure why but i know if they eat it then unlike ripped up tissue/tissue bedding, it wont sort of digest and pass though :L
it can also get tangled in their limbs which clearly isnt good, i know friends of friends hamsters who have died because of fluffy bedding >.<
i use ripped up (unscented) loo roll bedding
you can get it in shops too but in my local shop its about £10 for a sack D: so i rip it up myself
J-cloth bedding is also ok , ive never tried it thoughx