tulip side table  

Come on guys...
Can't anybody answer this question for me?

The problem is.....
The problem is getting to see an actual photograph of the table in question. The majority of vendors selling unauthorised pieces simply take images from Knoll, Fritz Hansen's or Vitra's website.
I'm not sure how many factories are knocking out the tables, but occasionally E-bay does have a photo or two of a side table. I saw one last week which frankly, was a mess. The circular base was iregular and the finish looked ropey. Most of them have marble tops, I'm not sure how refined the finish will be on the marble, but my guess is that it won't be great.
The only way to be certain of what you're getting is to go for Knoll. Or, if you must- find one of these companies that has a showroom where you can see the product- and, if possible- take it away that day. My guess is that a small number of factories churn out a large number of these tables.
I've got a Knoll version- it wasn't cheap, especially if you're in the UK (what is) but it was worth it.

From what I've seen,
the artistry of an original Knoll Saarinen table is noticable by its weight, balance and quality of materials.
I have an oval side table (often referred to as a cigarette table) that I found in a NYC Salvation Army, in 1992, for $15.00(!!!), and even though it's unmarked, it's a real one. I wish it was in better shape.
The white formica is high quality, the edge is crisp. The white pedestal has seen better days but is the perfect flat white color. The bottom is rusted and glides are basically gone.
I will make a photo of it and post it later today.
By the way, because the pedestal is made by Knoll, it's more slender than the vintage copies.
However, I DID buy a knocked off ashtray from Bauhaus To Your House two years ago and it has a lot of the same qualities that the original had, but it's sold without its screen insert. Also, the powder coat finish on the pedestal has chipped a bit...it was made in Italy, but the paint wasn't adherred to the pedestal the way Knoll does it.

I think
I think the long and short of it is; it's not that difficult to knock off the overall form factor of the table. But to do the table justice in terms of it's grace and elegance, everything needs to be perfect and refined. From the execution of the lines to the superior finish, Knoll ticks all the boxes.
It's a very beautiful yet simple piece of design but this stems from an acute attention to detail on every level. Like cheap look-alike Apple products- a lot of companies found out that just because you colour it white, it does not an Apple product make.

Here's my Saarinen table
on the left is the knock off ashstand, which weights about 1/4 of the original table.