Agree with this. Surface RT is painful. Especially office.
But Word, Excel and even PowerPoint are too much for it. Only good for reading. OneNote is very usable on Surface RT though, I do use that to take notes during meetings.
The Windows Mail app also sucks, and on RT you cant install Outlook.
But I've not found RT office to be unusably slow.
For me it lives up to its purpose of being a compaingion device.
The problems I have are basically the Mail app is uselessly bad and the Photos app sometimes grinds to a complete halt.