We don't. Here's a link to a parliamentary inquiry into Australian Air Superiority, where it talks about the change of status of JSF from VLO to LO.
Page 3 towards the bottom is the VLO discussion
Link
It points out that there is no recognised standard with regards to stealth terminology, which is why we are currently discussing this. Suffice to say,
from an Australian (and I believe US) perspective, SH and Rafale fall into the LO category, while F-22 falls into the VLO.
Anywayz, dealing with what is on the airframes.
-> The S-H has ducts angled along with tailplanes, and also co-alignment of most other detail surfaces to reduce reflectivity to certain planes.
So does the Rafale. Indeed, some major elements of its substructure have been shaped with reflectivity in mind. The S-H's has not.
-> The S-H has a screw within the duct to prevent radar hitting the compressor face.
The Rafale has a serpentine duct
-> The S-H has RAM incorporated onto various panels.
So does the Rafale.
There is nothing with regards radar treatment that the S-H has that Rafale does not.

Ok, I can’t post justification for why I believe what I do, so let’s just move on.
Passive acquisition
The F-22 relies mainly on passive acquisition to achieve the kill rates it does, why should that be any different for any other platform? Everyone
knows it is easier to see an active radar than be seen by an active radar.
[Don't anyone reply with that LPI pish - there are even books published on how to detect the damn things - check amazon if you don't believe
me!]

Well, there’s no point arguing then if you are going to dismiss LPI. We have an exchange officer with the Aggressor SQN flying out of Nellis who has
flown against the F-22, so I have a decent understanding of how such fights went. But if you don’t agree with LPI, I won’t argue.
Weapons
We are comparing aircraft here - since the Rafale can use AIM-120s, the point that the aircraft has inferior weapons to the Hornet is null and void as
it can use the same weapons.
(BTW - the AIM-120D is not in service, so is void as well - unless we want to start going down fantasy lane)

And there is no in-service Rafale carrying AMRAAM and Sidewinder. Consistency works both ways. Currently there are no users of Rafale who use AIM-120
and AIM-9, and we have to use this as our base scenario. If the Super Hornet and Rafale were to meet in combat tomorrow, the only scenario is a MICA
versus AIM-120/AIM-9X one. Anything else is going down fantasy lane…
[edit on 27-2-2008 by Willard856]