I have been highly satisfied with the SynchronizeIt! / CompareIt! combo from Grigsoft. http://www.grigsoft.com/
In combination with Total Commander (which has an excellent synch tool itself, though the ability to do multiple batches is missing) SynchronizeIt! works superbly and I prefer it much over BeyondCompare, because it is simpler and much more intuitive to use, while in combination with Total Commander SI has at least the same functionality at a lower price.
Also speed is excellent, and it supports rar, zip and 7zip (in latest beta). Synchronize It! and CompareIt! integrate very well also: When you want to see exactly where the files differ, simply double click on the file pair and CompareIt! will do its magic, even comparing ini files if the sections are in different places within the file (if set up properly with the ini plugin). Then you can do a merge operation if you want line by line or change by change. In the new beta even binary comparisons are possible.
If you use them via Total Commander, you make a button on the button bar and then when you click on the button, both dirs are synched or files even within the same folder compared.
Some more info on TC integration is here:http://www.grigsoft.com/art_totcmd.htm
SynchronizeIt! synchs folders, archives and FTP sites; it also has very powerful compare and synchronize files on non-connected PCs functions, logs and is very very fast. Preferences are stored in an ini file, thank god.
You can setup really complicated synch and backup jobs, exclude and include to your hearts content.
The interface is uncluttered and nicely designed. Download the current versions and then install the current (stable) betas/alphas over them, because the betas are bare bone programs only and this way you maintain help functionality.
SynchronizeIt! only costs about $14,50 or the combo with CompareIt! $29,50 and has a full function trial (the amounts are the 25% discounted prices by using coupon ICANSAVE).
The developer is very responsive and genuinely interested in helping his users even with complicated situations. Forum answers are prompt.
I have tested many synching programs starting with the Laplink for DOS almost twenty years ago, and I have found this software to be the best in the market.