I've been using Synchronize It! for a long time, upgrading from V3.2 to V3.5 today. Although V3.5 is significantly faster, there is still room for improvement. First, my system:
Intel i7 950 @3.06GHz, 3 x 2GB DDR3 triple channel @ 1600Mhz, RevoDrive PCI-e SSD 240GB, 2 x 1TB HDD Raid 0, nVidia 9800 GTX+ video
My primary monitor uses a resolution of 1920 x 1080. I've just compared two folders containing 50,000 files, where most of them needed updating on the dest. With the Synchronize It! window opened only just enough to view one line of files,
the scanning process took 20 seconds. When opened to "normal" size (showing 32 lines of files), the scanning process took over 80 seconds. The speed of the drives were around 50MB/sec and 111 MB/sec. When the SSD is involved (530 MB/sec), the difference is even more pronounced.
1. The mouse pointer is flickering between normal and wait states at least hundreds of times. This wasn't the case with V3.2. I have no idea whether this slows things down and even why V3.5 does this, but in any case it's annoying.
2. There is little point in updating the Synchronize It! window for each of 50,000 files. The only reason for viewing during a scan is to get feedback right? Well, any refresh happening more than a couple of times per second is redundant, as humans simply cannot read that fast. One way to handle this is to monitor real time in the scan loop, and skip any window refresh that's closer than say 100ms of the most recent, plus a forced refresh at completion of scan. If purists enjoy seeing blurred text fly past then add an option. Personally, I'd rather just do what I need to do and then move onto the next task.