Memory upgrade question

I'm considering buying a 20" iMac from the apple refurb store. However, it has 512MB of RAM, and I would like at least 1GB, if not 2GB.

Questions:

Is it worth buying this iMac and upgrading the memory?
If it is worth it, where do I get memory?
Do I get another 512MB or get a 1GB? (or two 1GB if I want 2GB)

Or does it make more sense to get the 1GB RAM iMac directly from Apple and upgrading to 2GB later if I need more RAM?

EDIT: I just went to Crucial.com, and have no idea what RAM to look for. Under DDR2, there is 2GB Ram for like $105. Is this what I am looking for??

EDIT 2: I just used the crucial.com memory advisor tool. I found memory that would work for $109.99 for 2GB. Is it worth getting the cheaper iMac 20" and putting in my own memory? And is it easy to do??

Thanks!

You do know there's going to be an iMac upgrade within the year right?

EDIT:
I read the post wrong, I see you're going for a refurb.

It would be a lot cheaper to purchase the 512MB model and then upgrade the RAM yourself. Newegg has Corsair 2GB PC5300 SO-DIMMs for $85. And according to GearLive, installing more RAM into the Intel iMacs is the easiest ever.

Edit: $65 for 2GB SODIMMs

softtack said:

It would be a lot cheaper to purchase the 512MB model and then upgrade the RAM yourself. Newegg has Corsair 2GB PC5300 SO-DIMMs for $85. And according to GearLive, installing more RAM into the Intel iMacs is the easiest ever.

Click to expand...

The G5s required you to take the back plate off, right? Someone told me you didn't have to do that in another thread (Cwa I think) but I remembered doing it and now I realized it was a G5, not an intel.

Title27GT said:

The G5s required you to take the back plate off, right? Someone told me you didn't have to do that in another thread (Cwa I think) but I remembered doing it and now I realized it was a G5, not an intel.

Click to expand...

Yeah, the G5's are a lot more complicated. I'm pretty sure kuklachica has the Intel iMac though because of the DDR2 RAM mentioned in the post.

Edit: I found that Frys has Patriot 2GB SODIMMs for $65.

softtack said:

Yeah, the G5's are a lot more complicated. I'm pretty sure kuklachica has the Intel iMac though because of the DDR2 RAM mentioned in the post.

Edit: I found that Frys has Patriot 2GB SODIMMs for $65.

Click to expand...

Thank god, I knew I hadn't gone insane at such a young age.

Does it matter that it says that this RAM is for notebooks? Or does Apple use notebook hardware so they can make the iMacs thin?

The Intel iMac uses SODIMM memory, which is normally used for laptops. They probably used it to save space like you said.