I already asked for some advice here about other components, and it looks like I'll be building a system using a fairly undemanding AMD Athlon 4050e CPU for now. The PSU is probably overkill even with a graphics card. However, what I really want to ask about is possibilities for future upgrades with this case and PSU, which I'm hoping I'll be able to keep in future builds. If I buy the Corsair, should its abilities hold up so long as the unit itself survives? I probably won't be doing SLI/Crossfire, especially not with power-hungry cards (I believe the PSU only has two connectors anyway), but I certainly might upgrade the CPU and/or GPU to somethnig that draws more power than what I'm building right now, so I want to leave some wiggle room. From experimenting with wattage calculators and trying to digest various FAQs, it seems to me like this Corsair should be a very safe bet for any non-SLI/Crossfire system, and possibly even work with some dual-card setups. But it would be nice to confirm that with people who truly know what they're doing.
I'm also wondering if the Antec sounds like a good idea. I looked at a few more expensive options, and aside from different aesthetics, there didn't seem to be a clear-cut advantage to spending more money. I'd like to keep the case below $100 if possible, and the 300 seems to have a good reputation. However, I haven't yet learned the tricks of managing temperature, so perhaps I'd be missing out on a case with better airflow?
Newegg has a coolermaster RC 690 KKN1 case for $69.99 listed in their 72 hour sale with free shipping when you use promo code EMCLWMM23. It's big enough for most components, and comes with front, rear, and side fans as well as bottom mount power supply slot. The corsair ps you listed should fit fine. Newegg also has some ps on sale.
Airflow won't be critical with the low-power parts you are using. The Antec 300 would be fine in either case.
For air flow, you generally want to a 120mm case fan (low noise/low speed/non-variable), a motherboard controlled 120mm CPU fan if possible and a graphics card that dumps heat out the rear. You should also ensure that your PSU does NOT draw air from inside the case if possible.
Find a PSU in your power/price range and Google it for reviews. Sites like NCIX have local consumer comments which are handy.