If you didn't have kdss on your trail, you will find the 100 a much nicer ride. Someone over on t4r called the 4r a more nimble drive, and I think that's a really good way to describe it. However, while the 100 is decidely more truck like in its steering and handling AND I just put e-rated tires on it, I am still in love.
I use it. I put my usual 300 lbs. of grain in the back of the LC this week and didn't even notice a difference in handling, while with the 4r, even with the airbags, I noticed the sag and compromised handling.
There is a huge difference between our 2002 and the 2007. I peeled out of the parking lot on my test drive with the 2007 by accident. It has a lot of power. I was planning on driving the 4R to Montana this summer, towing our 2k raft trailer, and am thrilled to have gotten this LC instead. I couldn't use my cruise control while towing with the 4r. That transmission never what to do.
There are significant differences in the quality of the 2 trucks, although I should say that I think the refreshed 5th gen was an improvement over the 10-13s (i had a 10). Everything about the LC reminds you that you are driving Toyota's best vehicle. The cabin ride is quieter, you don't have cheap plastics eveywhere, and there are some things about it that I can't even put my finger on.
Realize that if you love your audio Bluetooth, you'll need the Vais $300 addition to your own stereo because even the 2007 will only have Bluetooth for your phone calls.