2014 TRD suspension on 2008 RC ?

Long time lurker, first time posting here. I did quite a bit of searching but didn't come up with much so I thought I would ask the audience.

First a little background. I bought a 2008 RC 5sp 4x4 about a year ago with 18k, it now has about 38k miles on it. I do a lot of road trips, camping, and back road traveling throughout the NW. It gets loaded down with a sleeping platform, supplies for a couple weeks and also a bike rack and bikes on the back. I find the rear suspension extremely lacking, a lot of bottoming out going on and just an overall suckfest.

Here's what I'm wondering, would it be worth it to upgrade to 2014 or 2015 TRD suspension? I see a lot of guys with new trucks unloading TRD suspension kits with under 500 miles on them for like $400. They usually have it all; front springs, rear leafs (3 pack+overload), 4 bili shocks, and u-bolts.

What are everyone's thoughts? Waste of money? Worth the upgrade?

Thanks!

Side notes: I don't want to lift the truck. I know the rear springs are under recall but I inspected them and there are no cracks, etc, and other than looking like limp noodles, are fine. I also don't feel like waiting another 6 months for Toyota to make a plan to make a plan about the original plan..

Aaaand, a couple pictures to show what we're working with.

 

it would be an upgrade over the current setup, if you could get it at good deal. An alternative would be the 5100 for 200$ more.
http://www.headstrongoffroad.com/headstrong-kits-tacoma-05-6-lug.html

 

I've heard of folks doing this as a budget suspension option. A guy a couple streets over has a RC 4x4 and was talking about this the other day. Just so happens I have a set from my '14 DCSB TRD OR 4x4 with less than 1k miles that I was thinking about selling.