Our school went to a 1-to-1 system where every student has a Chromebook. So I'm currently typing on the Acer c720p that I've been using for about three years.
The Celeron in this model seems to be adequate for what we use it for. The attached screenshot shows the output of chrome://power, which looks like it can be used to get a rough estimate of CPU usage. During the period shown, I mostly was on email and Google Drive. According to chrome://system, the CPU on this model is "Intel(R) Celeron(R) 2955U @ 1.40GHz".
Additionally, top shows:
load average: 0.85, 0.63, 0.73
As far as the RAM goes, I've had to take the back off mine (the battery connector came loose, causing intermittent power failures) and the RAM is soldered directly to the mainboard; there's no way to upgrade it. I would suspect that the i3 model is the same way, though I have no evidence to support that.
Just a side note, if you want a touchscreen, I would suggest that you look at some of the other models; the touchscreens on this model is pretty fragile. Most of my classmates have broken their touchscreens, myself included. (I don't use it, so I never bothered to get it fixed.) Most of the time, it simply stops responding to touches, but I've seen a handful of cases where it sent random "phantom" touches that made the device unusable until they got it repaired.
If you have any questions about the hardware itself, I'd be happy to answer them the best I can, though since it's a school-issues device I can't do something like install Arch and see how it goes.
