ACA 1221EC Accelerator

[Oldsmobile_Mike]

its mainly gaming.

Specificity, folks. When you say "gaming", do you mean "playing simple games that came out in the 1980's", or "Doom/Quake/Breathless/insert name of game with high system requirements here"?

If the former, yes, it should be fine for WHDLoad games. If the latter... Well, you get the point. :lol:

[Oldsmobile_Mike]

Would it be worth purchasing if i wanted to upgrade my OS to 3.9?

You will definitely want some kind of accelerator for 3.9. The fast you can afford, the better.

http://os.amigaworld.de/index.php?lang=en&page=8

[Oldsmobile_Mike]

Does 3.9 work okay with WHDload?

You have that backward - the question should be "Does WHDLoad work okay in 3.9?" - Yes, yes it does.  

WHDLoad can have issues with certain cards (for example, very high end accelerators, network cards, GVP Spectrum graphics card), but not likely anything you're going to run into with a regular A1200.