I love 521s for their indestructability (well, almost indestructable. I only broke 4:p)
evry1 sed/sez DX32isms r cheese rims or really really heavy. well, yeah. they is noticably heavier till built up into a wheel and shoved on ur bike. remeber, a 521 wheel with mich comp tyre will b heavier than a DX32 wheel with light tyre. but hey....
I (reluctantly) went for an Onza Full Fat and...errrrr...YAY!!!!!!!!! when I started doin spinny street tricks, my tyre was folding loads on a 521 and causing me many spills. I haven't had a tyre fold since using a wider rim. and I don't notice the extra weight, even since goi to a nice heavy comp 16!!!
get one. yes 521s r brilliant, but DX32isms r just as good! tried and tested: FACT!!!!!
smithy