Tau crisis suits are so incredibly versatile, that magnetizing them is almost mandatory. What will you do after you've glued on that multitracker or flamer? Counts-as models are always a little bit of an admission of defeat, because you wouldn't pay enough money to have all the correct models.
However, using magnets maintains your ability to switch out weapons/systems on your battlesuits, without forcing you to buy extra battlesuits or weapons. You can also use magnets to make your devilfish/hammerhead/skyray interchangeable. An excellent tutorial on magnetizing your vehicle chassis can be found here.
I will be focusing on the XV-8 battlesuit, but magnet techniques can be adapted to just about any model. The model I am using has the forgeworld battlesuit forearms and weapon mount, but the technique applies to regular battlesuit arms as well.
