RetroUSB AVS NES Clone First Impressions

I just received my new AVS FPGA NES clone system from RetroUSB's Bunnyboy. This system differs from NES-on-a-chip hardware clones and RetroN5-style software emulation systems in that it is an FPGA-based hardware emulator. This gives it many of the advantages of a hardware clone (e.g., low latency, direct interaction with carts instead of dumping) with some of the benefits of a software emulator (e.g., firmware updates to add new features, etc.).

I won't rehash the info that's widely available elsewhere and will instead focus on things I haven't seen anyone talking about. But, just to get it out of the way, the graphics are perfect and the sound is just as crisp.

After facing a lot of compatibility issues with my original-run Analogue Nt and my Everdrive N8, the first thing I did was fire up my AVS+N8 to try some of the problematic games, namely Super Mario Bros. 2 USA and Ninja Gaiden 3. Both played just fine and I encountered no unexpected behavior.

Since the AVS doesn't do any expansion audio of its own--it just uses an analog-to-digital converter to pipe the audio from the cart or expansion device into the AVS A/V stream--it sounds as good or as bad as the original audio source. The N8's community mappers for Akumajou Densetsu and Gimmick! sound great, while the FDS expansion audio sounds...not so great.

There is also a screechy, sibilant thing accompanying certain sounds, but I suspect this will go away when I run the day 1 update. Speaking of which, it was harder than I expected to find the stuff needed to actually run the update. I didn't see any way to get them from directly RetroUSB.com's AVS page, which is where I would expect to find this sort of thing, but this post from NintendoAge has direct links:
http://nintendoage.com/forum/messageview.cfm?catid=106&threadid=166537
and you can sort through all of RetroUSB's downloads here:
http://retrousb.com/downloads/

To actually update the system, you have to connect the AVS to a computer and run the scoreboard application, which also includes a firmware uploading utility. Unfortunately, the scoreboard application is only available for Windows and Mac, which is a real drag for me, since I don't have either of those handy. Oh well.