Both of these products while announced a year ago seem to be of somewhat limited availability and there aren't a whole lot of in-depth user reviews online. I'd love to chat with someone who has one and demo it if possible.
The technology behind these provides an external bus to attach a double wide PCIe card such as the Red Rocket, so it can be interfaced with via the ExpressCard slot on your laptop. I've never tested this. Never even seen it but I do know how buggy and crashy ExpressCard is on MacBook Pro. I also can speculate that when you take a device that's optimized to work on 8 Lanes and slow it down to 1 despite the accelerating hardware in the box, there's no way it can achieve top performance. According to the Maxx site -
"Speed of transcoding to QT/MXF is dependent on the laptop processor speed. (ProRes runs at about 14fps from 4k)"
Even 14fps to ProRes along with realtime playback of R3D's over SDI is enough to warrant having one of these. My current laptop is a 15" MacBook Pro with a 2.4 GHz chip and 4 GB RAM (yes I know I need a new computer) and to render a full debayer from 4k to 1080p ProRes 422 takes about 45 minutes per 1 minute of RED footage. It's simply impractical do transcodes on a laptop, even a maxed out 17" MBP, without dedicated hardware like the Rocket. Time like that can be incredibly costly and can grind things to a halt. Post and Transfer houses LOVE getting drives full of R3D's because all that transcode time costs a fortune. A production I was working with recently had a month long RED shoot and didn't do anything with the files until photography wrapped. They handed a sizable stack of G-Raid drives to a well known post production facility and got a bill a few weeks later for $160,000. It's clearly advantageous for a production to do this on-set or to do it a facility that is equipped to transcode in real time. Namely with the Red Rocket, which zips on a Mac Pro Tower so even if it got to 50% of its potential on a laptop, that would be a massive improvement and in my mind, totally worth it.
My only concern is crashiness. I'd love to take one for a test spin or I might just take the plunge. A tower would be the smart thing to do but it's just so much stuff to haul around and I don't do enough RED to really warrant the purchase of a 6 Core with 12GB RAM.
I heard the video tap on the upcoming EPIC camera will be a clean (no overlays) 1080p. If that's the case, then great. Need on-set dailies or high quality offline media? No need to break out the Rocket, just record the video tap to ProRes with the upcoming Ki Pro Mini. Records to cheap Compact Flash cards in every flavor of ProRes and is only $2000. Get 2 and do one ProRes HQ for the editor and one ProRes Proxy for the director and producers. It's also the size of a Dionic battery. I think this little box is going to be everywhere. Why wouldn't you do a redundant recording in a high quality codec if it were so cheap and easy? (disclaimer - I'm also a fan of the NanoFlash which does some things this can't do.)