Aashish:
I am not certain what you mean by "accompaniment". See Page 36 of the FA-06 manual for selection and playing of Rhythm Patterns, but if you are expecting fully orchestrated auto-accompaniment "styles" like in an "Arranger" keyboard, then I am afraid that you are going to be sorely disappointed, as the FA-06/08 are not designed with those features. The Rhythm Pattern generator and arpeggiator do allow creation of some rather sophisticated patterns, but that is still more along the lines of a "beat box" or "groove box" or drum machine, rather than a full blown "Arranger". The FA-06/08 are fine instruments in their own right, but I just hope, for your sake, that you were not expecting a full "Arranger". If you were expecting a full "Arranger" and want to stay with Roland, then you would need the BK-5 or BK-9. The BK-5 retails for a little less than the FA-06 at about $1000 USD, but the BK-9 is rather pricey at around $2500 USD.
My concern is that many (most ?) of the online FA-06 demos contain backing tracks for the demonstrator that could give the impression to those who are not all that familiar with straight synth or workstation design, that they are "accompaniments" that are built into the keyboard, and they are not. They are professionally designed sequences that were recorded into or loaded into the keyboard's sequencer prior to the demo strictly for the demo.
Good luck !