Well... using SQL Anywhere 11. I don't have a concern with performance, per se, I'm just wondering if it's an acceptable practice to use functions to do the work of stored procedures. Other DBMS's create more of a distinction between the two.
It all boils down to 'best practices', I guess. We don't have any set guidelines for developing database functions and such; it seems to be at the developers' whim. However, those of us who have come from an Oracle environment tend to keep the two separate.