I had been using about 50-60% brightness and getting about 5 hours. At around 30-40% brightness I can get very close to 6 hours, but I've only tested this cycle a couple of times, I haven't had it long enough to really test it in different circumstances. 100% brightness I wouldn't be very confident in in all honesty.
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Yeah I can't argue much with that. In landscape mode I like the surface Pro's ratio better than the ipad, it's more widescreen so you can fit in more windows, this isn't an issue on the ipad because it doesn't have multitasking. In portrait mode the surface' aspect ratio is a mixed bag, both good and bad. It being very narrow it's terrible for web browsing, but it's actually very good for reading documents, working in Word, OneNote, marking up stuff with the stylus, etc. It all depends on the user as always. The ipad does have a nice balance of it all though and I wouldn't have criticized MS in the least if they copied that form factor.
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I don't have those games, sorry.
I did try The Secret World, it didn't run very well maybe 5 fps. I don't have as much high hopes for gaming as I did before I bought it, but I still have yet to try any other games and I've seen youtube videos of the HD4000 running modern games pretty decently. I'll have to play around with it. I have a copy of Guild Wars 2 I can test when I get time, those are pretty much the only modernish games I have.
As for OSx, I have a hackintosh setup on my desktop so I'm willing to try to hackintosh the surface Pro. All my computer stuff is in storage including my hackintosh disks and usb drive so it may have to wait. From what I've seen in the BIOS I don't see why a hackintosh couldn't run, but sometimes it can be very difficult to get those things to run and I'm not sure what would happen with the touchscreen drivers, or lack of them.