SourceAnywhere Standalone is much faster than SourceSafe:
1.When used remotely, SourceAnywhere Standalone is about 100 times faster than SourceSafe. When used locally, the performance difference is not so big.
2.The throughput of SourceAnywhere Standalone is much higher than SourceSafe, especially when you have high end hardware. When you have more users, the performance difference between SourceAnywhere and SourceSafe is bigger.
3.The bigger the repository, the bigger the performance difference between SourceAnywhere and SourceSafe.
After that being said, if your team size is smaller than 30 and you only use SourceAnywhere locally, the performance between SourceAnywhere and SourceSafe is not very big.
See the following white page for more information on the advantages of SourceAnywhere Standalone over SourceSafe: http://www.dynamsoft.com/Products/Reasons%20to%20Switch%20from%20SourceSafe%20(SourceAnywhere%20Standalone).pdf