- as stated above, the 740 is a rebadged [w/ custom firmware] BenQ 1640. This is no bad thing, since the BenQ/Philips 16xx line are excellent low-cost burners.
'Inferior' is a tough one: probably not unfair to say the 16xx BenQ burners can repeatably produce as good or slightly better results, with their best media, than the 716A. Also not unfair to say that the 716 will produce OK results from media the BenQ simply cannot cope with.
I've just ordered a 716A [despite knowing it is quite near EOL], & have owned several BenQ DVD burners [along with a raft of Plex CD-burners]: I didn't consider the 740 because you really are paying for the badge alone, until & unless the 740 has full Plextools functionality [unlikely].
Buffer size above 2MB in a 'burnproof' or equivalent burner is meaningless if the device is installed into a stable & adequate hardware platform.
A key plus-factor - in my decision to buy the 716A - is UDMA4 support: this should/might allow, in a suitable PL-3507 chipset external enclosure, 16x operation.