difference between on-line informix and SE

Hi all, I now know the difference between IDS and SE by reading all these messages that keep crashing into my mailbox. In fact I spend a fair bit of time trawling the mail messages for tip bits. But instead of waiting I was hoping someone may be able to briefly fill me in. Is the on-line product superior than SE. By reading the manual it seems you cannot connect to a different database using SE? Without reading the whole Informix SQL syntax manual I was hoping a brief summary might come my way. Grant