OL2003 has just about everything more than the OLEXP, including problem that you may find when you actually use it.
but since you have both programs installed, i think you should try the OL2003 and see how you like or can handle it.
this site is the Solutions Center for the OL2003 -
http://support.microsoft.com/default...;en-us;out2003
the OLEXP is not a bad email program at all, considering what it had been included in the program.
it's unlike the other in-built programs (likes system restore, notepad, CD burning tool... and some people may also think these programs are good enough for them already... they are all depend...), it's an or could be the only program that actully provide us the power to use it. it's for some people (myself included) who wants a simple and an easy to use e-mail, news reader and address book programs. they may not have so many messages per day, and these people are mostly home PC users.
but in the other hand, the business/corporate users will want and sometimes need or have to use the OL programs.
once you've tried the OL2003 and you found that it's not for you to use you can remove it, you can keep it but you would probably have to update it when using the Office update. a little off topic, but don't forget there still many email program out there waiting for you to try....
