Yeah it can be hit or miss. Kill Bill Volumes 1 and 2, pulp fiction and many others have been sold like this. Once the initial stock runs out you never know what you are going to recieve. The only way to know for sure is if it is listed as Steelbook, the problem is that they don't always list their items as Steelbooks even if they are! It can be painful.
It's just for TF1 releases. Otherwise, when ordering steelbooks from amazon.fr, I've always received steelbooks. It's hugely annoying though, to have this margin of error increasing over time with TF1 releases - no problem when the steelbooks are just released.
I got lucky on Valkyrie and Jackie Brown, they were both steelbooks. But I was hugely disappointed to get Immortel (ad vitam) in amaray. Since it has been a long time, back when I wasn't attentive about steelbooks, I also received Pulp Fiction in amaray but I don't know if the amazon page indicated it wasn't a steelbook - Immortel's page, however, did and still does say it is a steelbook when it's not, at least the one I got !
To my knowledge, TF1 hasn't released new films in steelbooks since 2011 at least. Maybe they did produce new ones of 3:10 to Yuma, there's no other page besides this one to get it on Blu-ray, but I'd be cautious.
On another note, I didn't know amazon had sold the Inception Dream Machine briefcase, I thought it was exclusive to FNAC in France. Anyway, that's where I bought it the day of its release on 3rd December 2010 at 12:45pm, only three were left in store and they weren't getting a new batch. I have #2152. I think that's the most complete edition that had been put out in the world, and one of the rarest. And even if it's not I don't care, I'm happy with my briefcase.