I know of no real reason to use a cheat grid if the final artwork is going to be vector, and don't see much reason to do it if the artwork is going to be raster (unless it will be strictly aliased raster artwork).

But the plug-in is not cheap, and you'd be mostly paying for its primary focus: multi-view ortho 'drafting' features. So far as plug-ins, as I recall, HotDoors CAD Tools includes an isometric grid. Inkscape includes a user-definable axonometric grid feature, and can be had for free. That program is inexpensive, and includes that kind of 'isometric' page grid.Ĭorel Designer includes a proper feature set to facilitate correct axonometric (including isometric) drawing. If you intend to use a 'cheat' grid, you might do well to take a look at Xara Xtreme. But you can build several such grids (for example, at several scales) and just turn them on/off as needed. The only drawback to that is, it doesn't span the entire pasteboard. If you feel you need a grid, you can simply construct one with open paths and either store it on its own locked layer or convert it to pathGuides. Using those devices, I draw directly in the isometric without need for a grid. In Illustrator, I set SmartGuides to 30° increments and use a few isometric Symbols (for repeatedly-needed elements), a drawing of a Unit Cube and isometric protractor (for true measures and off-axis rotations), and a couple of scripts.

I do alot of isometric drawing, and don't use a grid per se. If it's going to be raster images in final form, do you intend to draw it in Illustrator as vector artwork first, and then rasterize it?

Isometric grid illustrator