[SixOfSpades]

Well, let's talk about advantages & disadvantages.....

Fighter/Clerics can be of any race except Human or Elf. You may want to choose a Dwarf, Gnome or Halfling for the Saving Throws, but then you've got the Dwarf's -1 to DEX, and the Halfling's and Gnome's -1 to WIS. As previously mentioned, Dwarves can use the Dwarven Thrower, the only ranged weapon that can do Blunt damage. Still, the Thrower may have a very low Attacks per Round....I've never used it, but to me it seems to be an unspectacular weapon, and there's certainly no shortage of good Slings to be had.

As a Multiclassed character, you're going to be getting more High-Level Abilities than a pureclass or a Dualclass would: Each time either of your halves Levels Up, you get to choose a new ability, and both the Fighter pool and the Cleric pool are open to you. However, you're going to suffer a small penalty to your hitpoints, THAC0, and Saving Throws, as opposed to a Dualclass.

Dual-classing allows you a bit more flexibility: Apart from granting you access to the Berserker kit, you get to decide exactly when you want to Dual to Cleric. Some moments to choose from:
Fighter Level 2 -> Cleric Level 39: No real reason, except that you can use those "Warriors only" items like Potions of X Giant Strength.
Fighter Level 13 -> Cleric Level 38: You get the full hitpoint value for your Fighter levels 1 through 9, the THAC0 of a Level 13 Warrior, and you don't miss out on a single thing, Cleric-wise.
Fighter 20 -> Cleric 30: Characters' THAC0 and Saving Throws stop improving at around the 3 million EXP mark, so being a Warrior through all of SoA can give you the full benefit of a Warrior's Juggernaut Factor. As compared to Plan 1, Plan 2 means you lose 3 Level 7 spells per day. You get only one Fighter HLA.
Fighter 24 -> Cleric 25: Exactly like being Multiclassed, except that you can take a Fighter kit....and you lose out big-time on HLAs, and your Fighter half is buried for so long that it might as well not be there: It's not much use having a tremendous THAC0 if it's stuck in your Dual-class and you have to use your Cleric THAC0.

All of the above arguments apply to the Ranger/Cleric and Ranger->Cleric as well. The difference between Fighter and Ranger (in this case, anyway) are as follows:
1. As Rangers level up more slowly than Fighters, a Ranger/Cleric will have slightly worse hitpoints, THAC0, and Saving Throws than a Fighter/Cleric with equivalent EXP. If a Fighter and a Ranger go up to the same level, the Ranger->Cleric will have fewer spells than the Fighter->Cleric.
2. For some unknown reason, you cannot Dual-class Archers or Stalkers.
3. Ranger/Clerics and Ranger->Clerics have full access to Druid spells as well as Cleric spells. Even if you Dualed your Ranger before he was able to cast *any* spells, you will still be able to cast from BOTH halves of the Priest Scroll.