It’s as close to the real thing as you can get, the fact that there is more weight outside of the plates that actually touch the floor should make no difference because you will still have the same center of gravity. If anything, it might be slightly more unstable because the weight is spread out further.
Are deadlift bars all exactly the same or do some have more whip/flex than others? I know from experience that IPF competition bars aren’t all equal, I would expect similar issues with deadlift bars.
Oh and nice pull, I’m jealous of your leverages.