Below is a sample Elf Wizard/Fighter that I made up using my current version of the Armored Casting feat. It was very quick, so there may be some mistakes and the magic items are probably not completely representitive of a character of his level. I did 2nd, 7th and 12th level.
I don't believe this character could outshine a fighter or a wizard at pure melee damage(taking and receiving) or at spell casting(12th level wizard can cast Disintigrate and Circle of Death, while this guy is still stuck at Polymorph and Stone Skin as his best spells). At 12th level, in a single fight where he gets several boosting spells off, he can probably outshine a fighter(Hasted, Flying, Stone Skinned Fire Giant with a longsword!) but that probably doesn't have much to do with his wearing armor...And if he wasn't wearing armor, he could Whirlwind Attack, too!
****************Level 2*******************
Class/Level Wiz1/Fighter1
Abilities:
Str 13
Dex 15
Con 12
Int 15
Wis 10
Cha 10
HP = 10
Skills: 16 Wiz/Ftr4
Feats(1 Wizard, 1 General, 1 Fighter): Scribe Scroll, Armored Casting, Weapon Focus(Longsword)
BAB = +1
Saves:
Fort +3
Ref: +2
Will: +2
Attacks: Longsword +3 melee(1d8+1); Longbow +3 ranged(1d8)
Armor: Leather, Sm Wd Shield(Check Penalty = -2)
AC = 15(22 w/ shield spell)
Typical Spells: True Strike, Sleep*
*10% chance of spell failure
****************Level 7*******************
Class/Level: Wiz5/Ftr2
Abilities:
Str 13
Dex 16
Con 12
Int 15
Wis 10
Cha 10
HP = 33(average)
Skills: 20 Wiz/8 Ftr points
Feats(2 Wizard, 3 General, 2 Fighter): Scribe Scroll, Craft Wand, Armored Casting, Weapon Focus(Longsword), Expertise, Dodge, Mobility
BAB = +4
Saves:
Fort +5
Ref: +4
Will: +4
Attacks: +1 Longsword +7 melee(1d8+2); Longbow +7 ranged(1d8)
Armor: +1 Studded Leather, +1 Lg Stl Shield(Check Penalty = -2)
AC = 20(27 w/ shield spell)
Typical Spells: Shield*, Shield*, Expeditious Retreat*, True Strike, Bull's Strength*, Cat's Grace*, Mirror Image*, Haste*
*5% chance of spell failure
****************Level 12*******************
Class/Level: Wiz8/Ftr4
Abilities:
Str 14
Dex 16
Con 12
Int 16
Wis 10
Cha 10
HP = 51(average)
Skills: 48 Wiz/16 Ftr points
Feats(3 Wizard, 5 General, 3 Fighter): Scribe Scroll, Extend Spell, Craft Wand, Armored Casting, Weapon Focus(Longsword), Weapon Spec(Longsword), Expertise, Dodge, Mobility, Spring Attack, Improved Crit
BAB = +8/+3
Saves:
Fort +7
Ref: +6
Will: +6
Attacks: +3 Flaming Longsword +14/+9 melee(1d8+7+1d6 crit 17-20/X2); +2 Longbow +11/+6 ranged(1d8+2)
Armor: +3 Mithral Chainshirt, +2 Lg Stl Shield(Check Penalty = -1)
AC = 24(36 or 37 w/ shield, cat's grace & haste spells)
Typical Spells: Shield*, Shield*, True Strike, Magic Missile*, Expeditious Retreat*, Bull's Strength*, Cat's Grace*, Mirror Image*, Extended Shield*, Protection from Elements*, Haste*, Keen Edge*, Dispel Magic*, Polymorph Self*, Stone Skin*
*0% chance of spell failure
Also note that if he Polymorph's into a giant, his AC and Spell casting ability will suffer(although his melee damage dealing ability will increase).
Edit: Whoops! Got BAB and saves wrong at 7th level...