A few quick thoughts - more to come later.
I'm about 3 weeks into my love affair with quadcopters so i'm clearly not an expert, but i think i've been picking it up pretty quickly. my first quad was the , since my intent is to eventually get into fpv flying. i've also got a dromida ominus mid-sized quad and the nano quad. i had read a lot about the proto-x but decided to go with the x12 due to the size of the proto-x's controller - it's tiny... like, 3.5" wide tiny. holding it, i feel like andre the giant trying to play xbox. the x12 has a much bigger controller, in fact it seems to be trying to the mimic the size and design of an actual xbox controller (which at the time seemed to me like a good idea). the other reason i liked the x12 controller was that it had dual rates and a flip button while the proto-x controller doesn't. nice features to have, so i went with the x12. well, turns out the x12 has horrible yaw rates (meaning when you try to spin it clockwise/counter-clockwise, it's incredibly slow). i timed it at about 7-8 seconds per revolution, compared to the h107d's 3 seconds. big difference! yaw is not the only control you need to manipulate to turn properly, but it makes it a lot more tricky. anyways, i found out later that the proto-x uses the same control scheme as the hubsan quads. i couldn't find any info on whether it was compatible with the h107d controller or not, but i'm here to say that it actually is. in fact, i haven't yet flown it with the original estes controller. flying the proto-x with the hubsan controller feels very natural, and the quad responds very nicely. there is no flip button on the h107d controller, but there is a dual rate switch and the proto-x does indeed change its flight behavior in response to it. for one thing, this means that the airspeed and responsiveness increases, and for another you can do flips the "real" way, by slamming the right stick one way and then the opposite. the proto-x makes nice, neat little flips, and doesn't seem to lose a lot of altitude afterwards. close enough for me! obviously the video screen on the controller stays blank, but you actually get an unexpected bonus - real-time battery voltage readings from the proto-x. neat! oh yeah, and the yaw rates are on par with the h107d - turning this thing is a lot more manageable than the x12. this is using the hubsan controller, so i'll come back and update this review as to whether it still turns that fast with the estes controller. another thing i found, because i like to tinker with stuff, is that the blades from the syma x12 actually fit on the motor shafts of the proto-x (but - and this is very important - the rotation of the blades is reversed between the two quads, so you have to swap the props around to match). the proto-x props are 1 3/16" wide, and the x12's are 1 5/16" and have noticeably more surface area. that doesn't sound like a lot, but considering the scale of these things, it's quite a bit of difference. the only catch is that the syma blades will not work unless you remove the proto-x's canopy. the battery is held on with double stick tape, so you won't really lose anything except aesthetics and a slight amount of crash protection. honestly, i think it looks better without it. i haven't yet experimented enough to say what impact these larger blades have on flight performance and battery life, but i'll do a few comparisons and update here. needless to say, this is the nano quad i *should* have bought instead of the x12. oh well, live and learn i guess. i'm going to store this in the so i can get a little "over-caffeinated electric bumblebee" action in between fpv flights. looking forward to only lugging around one controller for both! and yes, before you ask, these really are "a few quick thoughts" - my reviews usually are much longer ;)