Well...let's see...
Last year I bought the 2011 Mach 5.7 X9 kit for a great price at a local shop, but there were some things I didn't like, so I ended up doing a lot over time. Some things were changed out with parts I had from a previous bike. Some parts were bought new.
Stock stem was ridiculously long and bar was stupid narrow. I had them replace the stem with a 75mm Truvative Stylo T40 at the shop before I bought it. I believe they put the widest comparable bar they could on it at the shop, but it was still too narrow.
I installed my Deity Dirty 30 handlebar and Lizard Skins Peaty lock-on grips. I've gone through several iterations of thick and thin grips before deciding that I really like a thin minimalistic grip for max control.
Replaced brake rotors with 203mm front/180mm rear Shimano ones with the aluminum spiders.
I took the Fox Float 32 150 RL fork to PUSH to be tuned for my weight and riding style and upgrade it to an RLC (fork dive on ledges and braking was scary before the upgrade). The fork didn't quite match up with the rear suspension at first, but now it rides great.
Added Specialized Command Post Blacklite dropper post.
I wanted to go tubeless so I put my Sun Ringle Charger Pros on the bike and changed the tires to a Bontrager XR4 TLR front and Specialized Purgatory rear.
The original 26-39 2x10 gearing was too high on the low end for the steep, long Colorado front range climbs (especially with bad knees) and they didn't have adapters to change the gearing yet because of the new BCD. I also wanted a bash guard. I ended up going with a 3x10 X9 crankset and installing an e13 turbocharger bash in place of the big ring.
Well with the change in gearing and 10 speed incompatibilities due to throw distances/chainring differences, I had to change out to a 3x10 front shifter and a new front derailleur when I changed the gearing.
I decided that 30 inches of bar width was just a bit too big for me for everyday trail riding. Put the Dirty 30s on the FR bike and got a Race Face Atlas AM in 28.5 inches which has been perfect.
I replaced the stock brake levers on the Elixir CRs with Straitline ones. They are so comfortable and look awesome! Pricey, but worth it.
Realized the stock cassette chewed completely through my wheel's freehub, so I did 2 things. Charger Pros had some issues with spokes loosening and disappearing so decided I didn't trust them. They will get new freehub and transferred to another bike (they only make aluminum freehubs for this wheelset though, lame). I had the DT 340 hubs clipped out of the stock wheelset and built into Stan's Flows by a local wheelbuilder. I bought a new 10 speed Shimano XT cassette with carrier to decrease wear on hub.
When tires started wearing out, I replaced both with the new style Bontrager XR4 Team Issue TLRs in 2.35 front and 2.2 rear.
Put on Bionicon C guide. Love this thing so far.
Oh hey, they have chainring adapters for the 120 BCD cranks now! I'm also getting stronger (and 22/36 low gear was just stupid), so decided to switch the old crankset that I never got around to selling to the new 24-38 with integrated bashring. The 3x10 with e13 bash went to my 29er hardtail as an upgrade where the lower gearing made more sense.
I put the old front shifter and front derailleur back on.
Well since I have a bigger ring again and my chain was worn out anyway, it was time to get a new chain.
Next upgrade will be a SRAM X9 Type 2 rear derailleur with the clutch (preferably when they have them in white to match the rest of my components and replace the current white one that came with the white frame). They do apparently make them in the other colors, but I've only seen grey for sale so far.
X9 TYPE 2 Rear Derailleur | SRAM