I currently just use a laptop, HP Envy 14. Its dedicated graphics, intel SSD, i5, and 8GB ram actually still serve me pretty well for moderate use photo editing, however I wanted something portable that could also play the occasional new gen game @ 1080p res when hooked up to my TV. At the time I bought the laptop, the 5650M could actually play the game out at that time, however now it's a little long in the tooth.
[CASE] First and foremost, I was looking for the smallest possible case that would fit a mid-range video card like the R9 270. I just started researching for this build at the beginning of the month. There were really only 2 choices that came up, the Silverstone SG05 @ ~10 liters, and the Ncase M1 @ 12.5 liters. Everything else like the bitphoenix and evga hadron were just a little too big, considering I wasn't going to put in watercooling radiators or huge tower heatsink.
However, not only was the M1 twice the price, it appeared the indiegogo funding rounds were over, so I couldn't get one quickly anyway, so that left the SG05 by default.
In terms of the build, the SG05 isn't too bad the work in. I will say though, cable management is quite tricky because there isn't much free space when all the parts are in. I had the cables tucked very neatly up until it came time to put in the video card, and realized it wouldn't fit due to how I had bundled the cables together, so I had to unbundle a bit until the card had enough clearance.
The PSU and 120mm fan (spins ~700rpm) are both pretty quiet. No issues for me. Build quality seems pretty decent.
[CPU] Originally I was planning to get the i5-4570 for $149 from microcenter, but when I got to the store, I decided to splurge and get the big boy i7 instead for a little more longevity for this build, and my workload for this computer is more Lightroom/Photoshop work which can utilize the additional threads, rather than games. I'm not overclocking, so the stock HS/fan has been fine for me.
[MOBO] All the Z87 mini-ITX boards are pretty similar, but the Asrock has an eSATA port. I think the other board that has eSATA is the asus deluxe board, but that was twice the price. Also, Microcenter had this one in stock and with CPU bundle discount, so it worked out cheaper than buying it online.
[RAM] Ballistix were on bundle sale at Microcenter as well, not really any more expensive to similar 16GB CAS 9 kits there vs online. No compatibility or stability issues.
[STORAGE] I was originally going to order the 840 EVO online for $160, but I impulse purchased it at Microcenter instead because I was impatient and wanted to get up and running same day.
As far as the storage mechanical disk goes though, I think maybe I should have gone for a 2.5" disk. The 3.5 7200rpm desktop drive is a little loud. IMO its the loudest component in the whole system when it is actively running. I have windows power management set to spin it down after a few minutes of disk idle, so it's not too bad now. Windows seems to do it with individual drives, so there is no issue with any lag on the primary SSD or anything.
[GPU] This was really a huge toss up for me, GTX vs R9. The $180 270 OC non-X seemed to bench almost as high as the $250 GTX 760. I play fairly basic games though, mostly racing and sports [i.e. grid 2, f1 2013, fifa 14, dirt 3, etc.] so I opted to save the $70 and get the R9 instead.
UPDATE: 120mm Silverstone case fan started annoyingly clicking after 3 days of use, so I replaced it with a Noctua NF-P12-1300. Just as quiet at 900RPM, but no bearing noise.