Jensen and Partners International* 1101 San Antontio Road, Suite 301* Mountain View CA 94043
Phone: (415) 967-3200* Fax: (415) 967-3288
The optimizer is quite good; it generates fast, compact code by making extensive use of registers to pass parameters. They include support for multithreaded programming and DLLs in all three of their target environments.
One particularly nice feature is that the IDE is completely configurable. You can change how the editor operates; you can change everything about what's on the menus and how they're layed out; you can add your own hypertext help information to the IDE. They also use a project system that is very different from UNIX style makes, or from Borland's system. After you get used to it, is much easier to use; it feels like you're programming the compilation process process. It is also easy to produce LIB files or DLL files (something I could never do comfortably inside Borland's IDE, which insists that the only legitimate target of a project is an EXE file.)
One of the features they advertise is a smart linker and smart method linker, that can supposedly avoid linking in code that is unused (including unused virtual methods). I've had trouble getting this to work in a completely reliable manner, but the code it generates without the smart linker is still pretty lean.