It really was the golden age of centers, and each was absolutely amazing in their own way. Olajuwon was probably my favorite, it's great to see a guy so big be sooo smooth. Plus he's about the most pleasant person in the world. He lead the league in blocks twice, rebounds twice and shots once.
But Shaq was probably even better, for all his size he was extremely fast, and a very good passer of the ball out of a double team. Of course he had one of the best teams in history surrounding him, something Hakeem the Dream never had. He was also a two time scoring champion, unlike the rest, he also lead the league in shooting % 10 times.
Robinson wasn't as powerful as Shaq and wasn't as smooth as The Dream, he was a nice middle ground between the two, and harder working than either. He could score a ton of points, was the scoring champ in 93-94 with 2383 points, more than Shaq, Olajuwon or Ewing ever scored in a season. But it's very close, in his best season Ewing scored 2347, Shaq scored 2344 and Olajuwon scored 2184. Robinson lead the league in blocks twice, rebounds twice, fts made three times, fts attempted twice as well as the scoring title.
Ewing was an absolute beast, especially with his advent of the one step then two-footed jump move that used to be traveling until one day it wasn't. But that's a bitter Pacers fan talking, he was practically unstoppable, and no one ever covered themselves in sweat like Ewing. He lead the league in rebounds once.
Best season stats
Olajuwon: 27.8 pts [93-94], 14.0 re [89-90], 4.6 blk [89-90], .538% [84-85]
Shaq:
......29.7 pts [99-00], 13.6 re [99-00], 3.5 blk [92-93], .611% [07-08]
Robinson: 29.8 pts [93-94], 13.0 re [90-91], 4.5 blk [91-92], .551% [90-91]
Ewing:
.....24.2 pts [93-94], 12.1 re [92-93], 4.0 blk [89-90], .567% [88-89]
Career average
Olajuwon: 21.8 pts, 11.1 re, 3.1 blk, .512%
Shaq:
......23.7 pts, 10.9 re, 2.3 blk, .582%
Robinson: 21.1 pts, 10.6 re, 3.0 blk, .518%
Ewing:
.....21.0 pts, 9.8 re, 2.4 blk, .504%
Their career stats are well worth a look.
http://www.basketball-reference.com/players/o/olajuha01.html
http://www.basketball-reference.com/players/o/onealsh01.html
http://www.basketball-reference.com/players/r/robinda01.html
http://www.basketball-reference.com/players/e/ewingpa01.html
As much as I loved Rik Smits, I don't think he belongs in the same sentence as those 4. He lead the league in fouls once. He averaged 14.8 pts, 6.1 re, 1.3 blk on .507%. At 7'4" he never had a season where he averaged 8 boards a game, and only 1 where he averaged more than 7. That makes Brook Lopez look prolific. Though he got the most out of what he had, and he was crucial to the success of those Pacers teams.
http://www.basketball-reference.com/players/s/smitsri01.html