Welcome to cruise chat if no one else has welcomed you yet!
As for your cabin choice, you can't really go wrong on deck 8 of the Victory. We were on her last June on deck 8 but we were in a Suite closer to the middle of the ship. Carnival's cabin are all the same in a given category, so unless it is an aft wrap balcony where you have a larger cabin and balcony because its in a corner, you won't find it to be any different than any other cabin. You may get a little vibration when the ship is docking and they use the thrusters, but that would be more noticeable if you were on a lower deck. You should be fine.
Carnival Cruise Lines:
Fantasy 90, Celebration 95, Victory 05, Conquest 05, Spirit 6/06, Freedom 6/08, Holiday 7/08, Victory 6/09, Valor 9/09, Dream 6/10, Splendor 8/10,Conquest 8/11,Magic 11/11,Triumph 4/12,Spirit 7/12,Freedom 11/12, Triumph 2/13 - The fire cruise, Magic 1/14, Freedom x 2 6/14
NCL Dream October 2006, RCCL Mariner OTS June 2007, Celebrity Silhouette 2013