Yeah I agree with Lizardman, Magnezone is better than Dugtrio overall. Magnezone has a great resistances + solid bulk which makes on your team a nice utility mon, not solely to "trap and kill" like Dugtrio does which really cant switch safely so you need a doble switch / sac something before, still Dugtrio loses to common things like DD Shuca Tyranitar, Agility Shuca Empoleon or Scarf Heatran which are mons supposed to trap.
Another thing that I hate about Dugtrio is that after to kill something is fodder for a lot of dangerous mons such DD Nite / DD Gyarados / Gengar / Breloom / SubSD Gliscor / OTR Zong etc while with Magnezone you have the option to use t-wave or boom w/ custap endure set because unlike Dugtrio is not needed using Life Orb or Specs because hits hard already which makes a mon more flexible.
Another thing that I hate about Dugtrio is that after to kill something is fodder for a lot of dangerous mons such DD Nite / DD Gyarados / Gengar / Breloom / SubSD Gliscor / OTR Zong etc while with Magnezone you have the option to use t-wave or boom w/ custap endure set because unlike Dugtrio is not needed using Life Orb or Specs because hits hard already which makes a mon more flexible.