thanks brother
As i mentioned in my 1st post that i very rarely change speakers therefore not expert in this field
However, X600 is the best among all i used till now, including Edifier R251 which was 5.1 but with 4 inch Subwoofer, while X600 has 7 inch Subwoofer
Some experts recommend Equivalent speakers of Logitech, like Z323 or similar, i personally never used Logitech, but their repute better than Edifier
Some says that mostly available Edifier nowadays are "Copy" and not Genuine, so you have to be careful
finally i never find a user of X600 who is not impressed with them