How do you feel about the 'Big Six' Items?

[littha]

Anyway. Assuming a permanant item gives a +10 bonus and a consumable gives a +20 bonus for 10 rounds, should the guy with the consumable still be penalised for using that item for the rest of time? That means he is permanantly behind his friend for basically no gain in the long run.

Considering that the consumable +20 is probably a staff or wand, he'll have 50 uses of it.  50 uses of +20 for 10 rounds vs a +10 all the time is definitely a good balance, since you generally don't need the bonus active every time, only when the challenge is sufficient.  If you don't like being "behind" in the long run, then simply buy the permanent bonus item.  If you'd rather have the ability to "burst" bigger bonuses, then get the consumable, and save it for when you need it, and potentially save other resources at those times.

It was only a hypothetical though I suppose it could be a potion or scroll (Upper level scrolls with high Caster levels can be extremely expensive). In either case tracking used item costs becomes a bit of a chore in a long campaign

The other thing with consumables is that they are worthless both before and after you use them. If they are sat in your backpack they are wasted money and after you have used them they are again worthless.

I can see where you are coming from but pricing consumables like that actually hurts some mundane characters (rogues especially of both the flask throwing and wand using varieties) a lot more than a spellcaster (who gets reusable spells anyway). A fighter might want to carry around a couple of potions to heal themselves but a cleric has no need to.

[veekie]

Yep, spellcasters generally use consumables not for burst power, but for solving whatever it is that they don't have covered at the moment. They've got more burst power than they have actions to use those in. It's mundanes, those guys who have to spend the bulk of their funds purchasing expensive permanent items, and then consumables to do certain things at all.