The function of the StudioFlyer is nearly what I needed: a single unit to contain my computer and some rack gear (I would have preferred two additional rack spaces), with the extra bonus (a selling feature) of casters and a retractable handle for improved ease of transport.
Understand what you really need before purchasing this unit. If you need to transport something from room to room within a fairly small facility with smooth floors, this might be fine. If you need to transport expensive audio gear in a traveling situation, beware, and here's why.
First, the hardware on this unit is brittle plastic. While I was rolling the unit down a paved slope, the rack suddenly snapped upright, in the process shattering one of the plastic feet attached to the lid. When the guitarist offered to help carry the rack, he cut his hand on the subsequently exposed screws.
The retractable handle never appeared sturdy to me, and I usually avoided rolling the rack because of it. I rolled it that one time because I was very tired, otherwise I carried the rack everywhere. When the handle is extended, it is not straight (at least not on mine); there's an obvious "bend" where one piece of the handle sits inside the other (similar to some suitcases I've seen).
After the infamous shattering foot incident, I looked inside the rack for shock-absorbing materials around the rack, i.e. springs or some other material or mechanism. I couldn't find any—if they're there, I couldn't see them. Compound this with the fact that the wheels are small and hard (or with apparently minimal rubber), and I immediately realized that if this case is rolled around over bumpy thresholds or cracked pavement, all that shock will be going right through my rack gear. Again, I never intended to roll this rack, but I have lots of helpful, well-intended colleagues who are inclined to roll it. I became so frustrated with the lack of quality in this build, that I removed the exposed screws from the broken foot (rather than replace the foot), as well as the remaining foot, and the retractable handle—thereby getting rid of more cheap plastic, as well as the temptation for others to roll the rack.
There are still two plastic spring handles that I'm considering removing. I might replace all of the above with other hardware, or just deal with it for now until I save up to have a custom case built.
When I use the rack at a gig, I use a metal AV stand to keep the rack high enough for me to access the computer during shows, but the surface area of the table is smaller than the footprint of the rubber feet installed on the bottom of the rack. The underside of the rack is slick, and the thought of a bandmate or a roadie or me bumping the rack and sending it toppling was a real nightmare, so I put a cloth on the table to create some friction. Trimming out a rubber shelf-liner might work. I realize this deployment might be unusual to me and that it isn't necessarily a design flaw, but it was another problem I had to solve, so I'm offering that up to anyone who might have a similar need.
The idea behind this unit is really good. I use a software-based keyboard rig, and this rack should be a great solution. I'm giving this rack one star, because it does hold rack units, and so far there doesn't seem to be a problem with it holding the computer in place, so that much of the form factor works so far, but I can't help but wonder when I need to start worrying about it. The low rating, though, comes from both the inferior quality of the hardware, as well as the disappointment that a marketed function is really just hype rather than a useful feature for a professional situation. Were it not for the wheels and the handle, plus the related sales pitch, my expectations would have been different, and I probably would have given the rack three stars.
I realize that we all face varying needs and circumstances, so again, buyer beware. I bought this case because at the time, it was the only ready-made solution for encasing a computer and rack gear that I could find. If you need a professional case to transport your computer and rack gear in a safe, reliable way, I'd recommend either separate rack and computer cases, or that you save your money and order a custom-built case, even if that means spending two or three times as much.
Since I began writing this review, I decided to pull all my gear out of the rack and place it in other racks that I had. With Sweetwater's invaluable help, I restored the hardware to its original condition.
While I was enduring my frustrations with this unit, the Sweetwater sales engineers and support team were very gracious, professional, and conscientious. I've been purchasing from Sweetwater for a few years now, and they've come to my rescue on more than this occasion. Onward and upward, then. I'm looking forward to my next purchase with Sweetwater.