The evaluation version has the following limitations
it only supports the 80x86 & ARM family : IDA Pro support a large number of other processors.
it will only load 80x86 & ARM PE files. The full version of IDA Pro will accept virtually any file, from Atmel ROMs to OS/2 LX executables. See our disassembly gallery for information about the additional processors, operating systems and file formats we support.
only the Windows GUI version is included in the archive. IDA Pro runs natively as a Windows GUI or console application and as a Linux Console.
the only compiler signatures included are the ones that can be used to produce Windows 32 PE files; the only type information included is for Visual C++ 6 and Borland C++ Builder.
the debugger contains a demo version of the ARM/Windows CE debugger.
Please see our ARM/Windows CE debugging tutorial
you will not be able to save your work, it will time out after some use, it will not disassemble itself.
The full version of IDA Pro is not limited in any way, comes with one full year of free e-mail support and one full year of free downloadable upgrades.
What's new in IDA Pro 5.1 (Feb 21,2007)
http://www.datarescue.com/idabase/ida51news.pdf
