I recently switched from Synchronize! Pro X (SPX) to ChronoSync 4.8 beta (CS). It took me some time to set up my (9) sync documents but I am glad I switched.
Some features that stand out for me are:
- Superb technical support.
- The ability to synchronize a disparate set of items using "resolve aliases at the top level". This is a very flexible way to specify a set of files and folders that are indirectly related, and allows for very easy reconfiguration.
- The ability to combine a sequence of synchronization documents into one container, to run them all in a specified order (SPX has a similar feature, that is even more flexible, but it is much clumsier to set up).
- It is very easy to exclude files and folders.
- It is deeply multi-threaded. For example one can edit one synchronization document while another is running. This makes the program feel very fluid.
CS has many features I don't use, including the ability to perform scheduled synchronization and the ability to synchronization over the internet.
There are a few minor annoyances. The first synchronization can be painfully slow (slower than SXP) if it involves a lot of files. Also, some settings are a bit clumsier than I would like. For example, to resolve aliases at the top level one must first enable resolving all aliases (usually a bad idea, and CS rightly warns you so) before enabling "top level only". Having it ignore .DS_Store files (a very common need) takes more work than I would expect. But most settings are clear and easy, and the excellent technical support takes the pain out of the few that are not.
The main reason I went straight for the beta (after trying and rejecting the program earlier) is the ability to reset synchronization documents. This is crucial to me because I tend to tweak settings over time, and changing some settings breaks the document (CS warns about this, of course). In earlier versions of CS one had to start a fresh document at that point (a nuisance). With 4.8 beta one can reset the document to fix it.
I am mildly concerned about Econ Technology's business model of "pay once, get all upgrades for life". That is very generous but seems intrinsically unsustainable. However, no software comes with longevity guarantees, and CS has been well supported for many years. If that continues, great. If not, the version I'm using should continue to work for many years.
Why I switched from SPX: it worked well for me for years, but the ability to configure synchronization a disparate collection of items has been flakey for most of that time. In the early days SPX supported resolving aliases at the top level (like recent versions of CS). I found that simple and convenient. Unfortunately that feature broke years ago, due to changes in Mac OS that the author refused to adapt to. Instead he added a panel for adding pairs of items to synchronize, which I found much clumsier. Worse, I found it nearly unusable because editing that panel usually caused the program to crash. Despite repeated reports of this problem over the years, the author has been unwilling to fix it. I had occasion to set up such a document recently and simply could not do it. So I gave up and switched. Once SPX is configured it is fine. The interface is dated, but in some ways it is easier to configure than CS. Once configured, it runs reliably and quickly. So it's worth trying.