FOX RP3
This rear shock represents all of the advancements that air shocks have undergone towards "suspension pedal awareness" during these short few years of rapid improvement. With 3 quite distinct compression settings, the RP3 is just a great all around shock with an easy in or out-of-saddle reach in most cases. I really enjoy this shock and especially with how easy it is to set up. Set it up and go, and then flip a switch every once in a while just to change things up.

The is perhaps the most tunable of all rear shocks that I have ever tried, mostly because of the external compression settings which allow you to simply reach down and flip a switch. The nice thing specifically about this rear shock is that each of the adjustments actually seem to work and make a noticeable difference (not true of all high end products). The difference between up hill climbs and fast single track is a mere ProPedal position change, that allows the shock to open up freely and become nice and reactive. Then for the occasional 3-6 foot drop, adjust the ProPedal down one more setting and you're in business - and business is good!

The ramp up rate on the RP3 is a tad difficult to get your hands on to tune, but it seems neither harsh nor plush. It definately gets my vote over the highly sought after DHX Air where overlap might be appropriate in all mountain applications (which is such a rapidly frowing sector ofthe MTB populus). Unless you're doing 5+ foot drop on a very regular basis, this is such a nice way to go.

FOX DHX AIR
This rear shock represents all of the advancements that air shocks have undergone towards the "air can feel like coil shocks" movement. And I have to admit, as a coil coil, this certainly reacts more like a coil than I ever thought possible. The one disclaimer that I will make though is that the ProPedal might be a little disappointing, as this truly seems like a geniune DH rear shock (just my opinion). The advantage to an all mountain or freerider though, is that you just can't find a coil shock quite this adjustable (perhaps a little different than tunable, but along the same lines).
I have found that this shock is not an easy one to set up, and then not quite as tunable as I was hoping, though adjustable. The differentiation that I make between adjustable and tunable can be described as such:

• Adjustability = the ability to change the feel and reaction characteristics of your suspension
• Tunability (if it's even a real word) = the ability to get your suspension set up exactly the way you like it ... if you can't tune the suspension to your desired feel, the adjustability means little

So in this sense, the DHX Air can be changed to feel differently, but may not come out feeling exactlty perfect for your application - the range is limited. I'm even so sure that the ProPedal really works on this shock or not (as I've briefly tried this shock on two different bikes), but that's also with my expectation that in having 15 ProPedal settings, surely one would suit me well enough. Not as much as I was hoping.

That said, there's a much more impressive side to the DHX Air - dropping it. While on a ride down some winding singletrack that weaves in and through a stream 10 times over, I had the lovely experience which made both the trail and the bike get just that much more interesting. Screaming down a particular section I noticed that immediately around the next corner comes an elderly gentleman hiking up the same trail I was headed down. As I turned the corner, I opted (with a great big smile) to angle the bike up a steep embankment and drop off about 2 1/2 feet into the water, not having any idea what lay underneath the blur of ruching water.  I hope in vain for two things: 1.) that it wouldn't be more than 6 inches deep or so; 2.) that the landing would be unusually smooth beneath. Neither were the case as I found my wheels buried easily up over hub (probably about 15 inches deep) and rocks galore abounding there, sitting, waiting to thwart my fun. The DHX Air stepped in like a true superhero to save the day! Not only was the initial landing handled with superb plushness (a balance of used travel but ramping resistance), but it also proved extremely reactive to the incredibly uneven, rocky terrain. The rear wheel must have traveled up and down several times within that short second and a half without ever throwing any of that force back into the bike! Wow, that is a rare performance quality!

While the DHX Air is not the rear shock for me as an all mountain rider that does a lot of XC pedaling, surely it will not disappoint you extreme all mountain and freeriders because for the right application, this is one sweet shock.

CONCLUSION
All that this really proves is that there really is no one perfect rear shock. Then again, shouldn't we already know that?