Vandersteen 2ci and 2ce

There was a slight change in the cabinet of the 2Ce vs. the 2Ci. The tweeter was changed from a 3/4" in the 2Ci to a 1" in the 2Ce. However, let me warn you of a small caveat. Some of the tweeters in the earlier 2Ce's are the same ones in the 2Ci. You would have to check with Vandersteen using the serial number of any potential used purchase. I don't remember how far into the production run this went but it did go for a little while.
I would also consider the 2Ce Signature. It uses the tweeter out of the model 3A and a few other enhancements that make it the best sounding of the 2 series.

Shoe, The 3A Sig uses the tweeter and basically the same midrange out of the Model 5 speaker(not 5A) and the associated crossover. RV said that the drivers in the Model 5 are "Cherry picked" and the others go into the 3A sig.
The 2ce Sig uses the same midrange driver as all of the 2 series with the differences in the tweeter stated above.
Sonically, the 3A Sig is much more open and refined than any of the 2 series. It will play louder and produces a bigger soundstage. You get about 90% of the Model 5's sound. It is truly a wonderful speaker.
I have gone from the 2Ci to the 2Ce to the 2Ce Sig and then finally to the 3A Sig. Each has been a marked improvement in overall sound but the jump to the 3A Sig was a leap compared to the others. I'm planning on the 5A's this summer.

Aedv8sc is absolutely correct. The addition of a pair of 2Wq subs with the inserted filters makes a great speaker even better and the subs provide a solid bottom to below 20hz. I use this combination myself currently.