Sell 4850 x2 for $130?

The HD4850x2 will be more powerful than any of the cards you listed. The disadvantages are high power consumption, lots of heat, some crossfire scaling/compatibility issues and no DX11.

well im idling at 42C with the fan speed on automatic. it goes to like 35C with it on 100% and the highest I've seen while gaming is 52C or so. Is that a good temperature?

I've got a 700W OCZ Modxstreme pro psu that should be fine for a long time with this video card.

Another problem is the video card is probably flexing about 1/4 of an inch upward because I had to take the casing off the video card for it to fit into the case without moving the HD cage. The very bottom of the video card is sitting on the HD cage causing it to flex upward 1/4 an inch. Is that ok?

The flexing will shorten the life of the card. There can be a small flex and last for decades but that much will worsen the effects of cold hot cycles when the machine is used.

Sell your card and get new one like HD5xxx series, less heat, less power consumption, dx.11, less noise...

Yes, with 100% fan speed, you just shortening your card lifespan...

What? I'm not using 100% fan speed? It idles at 42C with fan speed on automatic. And 35C with 100%. I'm just doing automatic which is like 20% fan speed.

It probably speeds up on auto when it gets warmer from gaming. if this annoys you, you may be able to mannually set the fan speed in Catalyst Control Center. I found the auto fan speed highly annoying on my 4870, as it would ramp up to 70-80% fan speed during gaming. A non-auto setting of 45% is quieter than my case and CPU fans, and keeps it below 80c on furmark HLH. You may be able to find a similar comprimise if it is of concern.

If the 4850x2 performs well, don't sell it. Anything you might afford below a 5850 would be a downstep, except of course, in DX11 titles. The difference compared to DX10 so far has seemed minimal, and there are many theories as to why, but if DX11 is important for you to have RIGHT NOW, then of course, sell the card.

I think I'm going to stick with it. I'm not really a hard core gamer any way, that's why I sold the 5850. It was just too much for me. a 4850 X2 will play every game I own at 1600x1200 res and I mostly play Tf2 and mass effect 2 any way.

By the way, I sold the Desktop for $450 and the ram for $80. So I got $530 + a 4850 X2 for a 5850 that I paid $240 for. Haha  

Nice deal, hah.