"not particularly different" is a correct and usable phrase in written English.
You can use it to emphasize that two or more things are not substantially different from each other. For example: "The two versions of the test were not particularly different."
With the keyboard at the correct height, I felt my typing position was comfortable, and my posture was not particularly different from the one used when reading books.
Although the CBS epidemiologic investigation is in a very early stage, Dr. Ostroff said, "certainly the circumstances that we are aware of to date suggest that things are not particularly different there than they are at the other two networks".
The story O'Donnell tells is not particularly different from other startup tales.
This portion of the course is not particularly different from any other evolution-based course.
As a Hungarian, she feels not particularly different, because she does not behave particularly different or look particularly different.
But Snapchat, Chudnovsky says, is not particularly different from any incredible growth story on the consumer Internet going back to the days of Hotmail.
As far as that goes, 21 Grams isn't particularly different from the usual Hollywood fare.
Other than crucifixes on the walls and marble Madonnas in the lobby, Catholic hospitals do not look particularly different from secular ones.
Although it was criticized for not being particularly different from Kesha's previous work, reviewers felt that the song was a strong dance-pop number that combined a good rhythm with an inspiring message filled with genuine humor.
It's situated on a latitude similar to Newcastle and, barring the lack of humidity, the climate doesn't seem particularly different to home in the tamer months.
There wasn't anything particularly different about the making of this album.
