Best $4k upgrade on your FJ

6 months ago I think I spent the best $4k on my FJ with a Walker-Evans suspension upgrade and KM2 tires. Good difference on the road but GREAT difference off-road.

When I bought my FJ in 2012 I spent $3k on ARB 's and Smittybilt winch and that has been put to great use 3 times so recovery means a lot too.  

In other words, its hard to define which is the best of the 2 because of the differences. I could have been REALLY stuck without the ARB bull bar and the winch on 3 occasions, but the tires and suspension are a great upgrade EVERY time. See how I am torn? 

What do you guys think? Whats the best $4k you spent on your FJ ? And why?