Buddy you can remove psjailbreak/psgroove usb dongle after installing backup manager but you have to use psjailbreak/psgroove usb dongle every time u start ur ps3. Its already been answered several times that even if you use jailbreak once sony will know it bcz ps3 generates a log file/files that has the information about what recently you have played on your console.
They can ban your ps3 from psn but so far they didn't ban any ps3 they just rolled out a firmware update which will block the jailbreak exploit (which they recently did with 3.42).
As for solution to prevent your ps3 from being banned you can make backup manager ninja, you can find more infos here... http://www.ps3news.com/forums/ps3-gu...er-112443.html
If this helped you plz give me a rep by click on green button and then by choosing i approve.