What still cameras WITH VIDEO have the Past Movie feature like Casio Exilim EX-Z750, but have more than 7.2MP?

I have a Casio Exilim EX-Z750 with this Past Movie feature, which is great because what it does when you pick that VIDEO recording mode is stand by while recording a continuous 5-second loop until you press the “take” button, which then sets that last 5 seconds down permanently and continues on with the rest of the recording. This is great for recording when you anticipate a sudden motion but don’t know exactly when it’ll happen, and also don’t want to already be recording up a bunch of memory just in anticipation of the sudden action.

But now these still cameras with video on the side, whose still modes have 8, 9, 10, and 11, etc. megapixels are becomong more mainstream and less expensive, and I think it would be nice to buy myself one of them with the even higher resolution for still pictures than this 7-MP camera already has, but I want to make sure it has the Past Movie video feature as one of its side benefits. Unfortunately, Casio stopped including this feature when they made their EX-Z850 and 1000 and on; and why, I don’t know, but that’s frustrating to me. Who knows of a brand and model that does have a feature like this but is higher than 7.2 MP (and is also about as physically small as the Z750)?

Also, while we’re at it, what models of ACTUAL video cameras (the kind of camera whose primary function is shooting video instead of stills, but may be able to shoot stills as well), in HIGH DEFINITION, has a mode like this Past Movie mode (which would mean that it would have to be able to record HD video onto a card or a hard disk or a rewritable optical disc, rather than just a tape)?

Will you come back and see my responses to your answers, please?

Thanks,
Mike Christensen
Hey, Iridflare, you must not have paid very much attention to what I wrote about why I want what I want. I already explained why I think Past Movie is important. You don't always want to keep recording until you get what you want! It eats up space too quickly and you don't always have time to stop and back up over the stuff you didn't want to keep! Go back and REread my explanation!

The video camera with a feature that like Casio's Past Movie feature would HAVE to have a form of storage besides tape because tape is sequential and cannot run in a loop mode and then suddenly switch to continuing on "down the road" from there like chips and disks can. In fact, maybe optical discs wouldn't be able to get written and then rewritten for continuous looping and then progressing past that as soon as the button is pressed. But there are already hard-disk-based and memory-card-based HD video cameras. Now I just want to find one that has this feature. It would come in very handily!
So, Iridflare, how about paying more ATTENTION to what someone writes before you make yourself look like an idiot with a careless answer?

And actually, the more pixels you have in a picture, then the sharper a picture you can have in the same size of space, because there are more and smaller dots; OR, the bigger picture you can have before getting jaggedness (not that I need to blow my pictures up very often), OR, the more dots in a picture, the more you can examine a photo for some details that you wanted to check out later after you've shot a picture and even after you're away from it. So NO, you're wrong, the more megapixels a camera has is NOT overrated.

Now, does anyone have a REAL answer to my question?
True, though, pixel count isn't EVERYTHING that makes the quality better, I know that. But if my camera were breaking down and I was going to buy a replacement anyway, it might be a good idea to upgrade to more pixels IF the upgrade didn't cost much more nowadays (though it used to), and if I can find it with the specific feature I'm talking about. If not, though, then yeah, getting a replacement of exactly the same model wouldn't be too bad, really.
But oh, Iridflare, I do ow you one thanking, and that's for the web link. There is some interesting material there.