I think Vikramshila is also a good train to travel from patna to Anand vihar as it's speed & stoppages are comparable to sampoorna kranti.....I had travelled in this train 4 years ago & it reached delhi just 1 hour late....at that time sampoorna kranti was facing some issues & was running hours late daily....but now conditions have reversed & VS is facing same problems especially in the ncr area....yet it is a good train...so my vote goes to Vikramshila...