I have used both the h10 and the creative zen micro. I would DEFINITLY recommend the creative. The h10, since i have had it, has frozen up and is just plain painful to use at times. The creative zen micro is smaller and very user friendly. It, like the h10, has a removable battery and great battery life. I don't know about the dell, but i highly recommend the creative and strongly advise against the iriver. Hope this helps!
of the 3 above, which is the best bang for the buck, easiest to download music to - i like the IRiver H10 (5g)- my husband things the Dell DJ because I have a Dell Inspiron laptop - i've tried to compare the 3 together and am now totally confused - please help us - it's for our 12 yr old son!!!