mteolus, no contact between the diff skid and the trac bar? Steve has been helping me to trouble shoot some contact between his trac bar and my diff and he said the diff skid could be a problem

I can't think of anything disappointing, regretful, or negative effects from going to 285s. I love mine.

Wait, I lied. The logistics of figuring out whether you need a BMC and/or UCAs was the biggest "challenge" from a time perspective for me. i.e. how many times do you want to lug your 4runner to the shop?

You might not even need a BMC or UCAs -not everyone that goes to 285 needs them, but I imagine that depends on your usage and suspension travel. I think the process would go something like this:

* Put on 285s
* See if they rub and if so, assess mod what you can e.g. remove front mudflaps, splash guard mod, and probably trim some of your front bumper (keep in mind, if you get UCAs down the road, you might have to trim some more of the bumper depending how much clearance you give yourself the first cut around)
* With my bilstein 5100s and stock UCAs, I can't get more than 1 degree of caster. So, it'll be a toss up at this point whether you get one or both re: BMC and UCAs. If you get the BMC, you can forget the UCAs altogether since you'll have clearance, but if caster means anything to you, UCAs might be for you.
* If the BMC bothers you at all (e.g. I hate rust and the minor rubbing that occurs brothers me less than potential rust from a less-than-perfect BMC job so no BMC for me), you might want to try the UCAs first. All depends on your comfort level.

Or, you can commit to both and get it done in one quick trip to a shop and be done with it. Super fast peace of mind.

I don't do anything hardcore with my runner so I put up with the little bit of rubbing at full articulation (more so in reverse). The front mod/splash guard rubbing is starting to bug me so I'll take care of that in the spring (I run OEM sized winters during winter).

$0.02