I've only seen Metal Fusion which I found pointless to watch but I'm always engaged since it's on TV.
I don't remember watching the original series but do recognize it \;

For the most part I've only seen the original Beyblade series when it was on TV..if I recall correctly it was on Toon Disney or something like that..

The original series of course

i loved this series. metal fusion was not bad. plus, my favorite character is in the original series.

I tried looking for the original series on the internet, but I didn't find any episodes in english... Plus, my favourite character is Tsubasa from Beyblade Metal Fusion and I like him even more in Metal Masters ^^