For that same $387 US, I can get on ebay and buy a real oscilloscope that's not a toy, one that has 2 or more channels, at least 100MHz bandwidth (or as high as 500MHz), a fantastic timebase and triggering system, fast risetime and good sensitivity.
The USB toy that you've cited would be fine if it weren't so expensive for what you get. The sensitivity of 3v (Per division or what? It doesn't say.) with a 10X probe is nothing to the worst-case 50mV/div that you'd have with a real scope. And beware that phrase "1GS/s equivalent time sampling, repetitive waveform". That's not the same as a 1GS/s single-shot sample rate. And anytime you use a PC based scope, you have to have a PC attached to your "scope", which in most (but certainly not all) cases can be cumbersome, inconvenient and very non-portable.
Are there advantages to this USB product? Sure. Because of the power of the PC and the supplied software, it should (it better) give you some waveform storage and waveform calculation routines. But for the price, that's about it. I'm not trying to knock your product discovery. I'm just a guy who's used neary every type and sophistication level of oscilloscope (although I have yet to lower myself to a PC-based scope, so there is a bit of bias here) for the last 40 years.
There's just so much fine, used, serviceable, high-end, lab-grade equipment being sold on ebay and going for a song that I hate to see anyone buying this expensive, new stuff that is so poor in performance!
And when that USB toy goes defective, you are totally screwed and out your $387.
Update: Sorry. I just realized that it was $387 for TWO of those. That means that they're selling them as a pair to make you think you're getting two channels but are really providing a spare for when the other goes belly-up! Those two channels on separate USB ports are probably not going to allow the high-speed timing and phase comparison that a conventional scope (or a true 20channel USB model) will provide.
Still, it takes $387 to get the "two channel scope".
Dean