i was confused by mpod's original comparison, because it wasn't a comparison, as has been noted. but his follow-up was good as it showed the difference between what arturia aims to recreate and the original. it inspired me to see how close i could get with adm and drumazon and in both cases was disappointed. so for now it seems you need the real thing or samples if you want that sound. apparently 909 kick synth emulations are harder than one might think.
i think the people here saying that time is better spent on making music than researching sounds are missing an important point. the reason the 808 and 909 are still used is also because the are so easy to mix, as mpod noted as well. so the original or a good emulation will help you in the production process. you will spend less time tweaking because the thing just works. a bit of research buys you time when you really need it: when inspiration hits.
of course, 808/909 aren't the only usable drumsounds. arturia might have made something that is on the same level, but different. but trying to find out what makes the 808/909 tick will make you a better electronic music producer.