the best extract is the one with the longest use by date (from today). never buy from the 'approaching use by date' special bin. been there, suckered in. stale cack, and just to make sure, i did it twice. kit beer ages and deteriorates, and taste is stale, tinny, slightly acrid off. or you could try one and see. you'll never do it again Lol. you'll never be able to share it with your mates, you'll have to drink it all yourself. as punishment.
more expensive than coopers - quality?? not necessarily. maybe more expensive specialty malts in there. i think i liked a morgans bock(???) which was a cut above, but that's my tastebuds, too.
i suggest that whatever you buy (coopers, morgans bock included) is to incorporate some steeping hops in (reams of stuff here on that, i'm sure). you don't need much, it'll get you researching hops, and it certainly lifts a kit brew for flavour. steeping some crystal grain (aka caramel grain) is another good flavour and stability boost. maybe 30gm, if i remember, and you do that while you're bringing the wort to boil, then add the steep in for the last few minutes of boil for flavour.
if you do the hops and grain steep, you'll make anything in a kit taste a lot more sophisticated, and it puts you on an 'ingredients and styles' learning curve. you won't learn much about ingredients and styles by tipping a can into a pot.
but rule #1 is always tip the can over and check the use by date.
