I was doing some quick searching and realized I couldn't find a conclusive answer. Hardtrailz switched from 88 to 89, Regulator was looking for 88s hardcore at one point.. I'm not sure what to make of it.
Now that we have the availability of 87 and 88s, would it be more beneficial to go with one for armor (bumper, skids) instead of 89s? I know the question is kind of vague, but I can't decide between 88s or 89s for front bumper/skids + lift, and would rather swap out springs once. The chart tells me there's only ~.15 inch difference on wheel lift (coming from 81), so in theory it really shouldn't matter. If that's the case, I'm saving myself ~$80 and going with 88s.