The new ZoomFloppy is the successor of XUM-1541 and all X-cables (X-1541, XA-1541, XM-1541, XAP-1541, XU-1541, XS-1541). With ZoomFloppy you can connect all your Commodore drives to your PC using USB connection.
ZoomFloppy can be ordered from Jim Brain in his shop: klick (http://store.go4retro.com/products/ZoomFloppy.html)
ZoomFloppy supports of course OpenCBM software. But new is, it also supports nibblecopy (MNIB) to create better disk images (exact images). For this a parallel cable (Speed-DOS) is nessecary, same type used by XAP-1541 cable.
It will also support old CBM drives with IEEE-488 bus in future.
According to the presentation that was given at ECCC, the ZoomFloppy will support nibbling with a stock 1571 over the IEC bus. The guy did a pretty thorough presentation on the awesomeness of the 1571 when running in native 1571 mode.
I'm wondering about this.
1571 burst mode is planned. But in current source files is nothing about. I will ask Nate about this.
I'm sure you have seen a parallel 1571. My parallel 1571 is very very fast. Also my parallel 1541, especially in MNIB mode.