I currently own and LOVE my (pink) Acer Aspire One. I paid $350 6 months ago through
Walmart online. It is very quick setup and easy to use. I have MS Office (fulll suite) loaded on it and use it exclusively for all emails, household budgeting, and college work. I am a full time student majoring in English and History so I do a HUGE amount of research and papers. The battery lasts about 90 minutes while I have everything running at once, but I am usually near an outlet so I just plug it in anyway. I could spring for a better battery, but I probably won't.
I will say that while it is plugged into an electrical outlet, it is BLAZINGLY fast. I mean FAST. However, IE runs slow(er) when the computer is running on battery power. I don't know why, but I do know it is not just me. It is still acceptably fast, though.
Two things in particular:
1. Mini PCs are mini, which means the keyboards are small. For me it's a non-issue, I am a violinist with small hands, so I can fit them where they need to be. For my husband with big hands and large fingers, it is a problem. He can't use it without hitting 2 keys at once. It is possible to hook a full size keyboard up to it if needed, but it kind of defeats the whole portability issue.
2. Minis don't come with internal CD/DVD drives. The point is for them to be lightweight, fast, and portable and extra drives work against all three. The Acer Aspire Once has three USB ports, however, so I can hook it up to external drives when I need them.
Like I said, I love mine, don't know how I got along without it before. It even fits on the windowsill in the kitchen so I can look up recipes or have music playing while I cook. It isn't for everyone though. DH won't use mine unless it's the only option. He prefers his hulking Toughbook.
Hope this helps!