I've painted all my tanks. I used to use the backing and tape it on. Over time, you will keep having to replace it -- especially if you have hang on equipment. Salt gets between etc.... backing deteriorates, water gets splashed etc...
Painting is not fun, but lasts -- you can always razor it off -- not difficult at all. Most people paint it black or a rich blue. If you do decide to paint it, make sure you clean the glass with alcohol to remove any oils (your hands have oils) using latex gloves. Paint it the color of your choice -- I use rustoleum sail blue -- a few coats and a final coat of black. Also, before painting and using alcohol, make sure you silicon the top and bottom ledgers -- if you don't the paint will seep into the frame. Also, tape off the side and top so overspray does not get into tank.
That said -- yes it is a pain in the #@*, but not as much as having to try and apply backing to my 120 or 155 with 4" of wall space.
Good Luck there is no right or wrong answer -- to each his own