I've been using an old iPad for many years and generally find it OK for web browsing, watching videos and so on, but even with an external keyboard attached it sucks for "PC like" tasks. Maybe I'm just an MS slave, but the Office apps are hard to beat, and the limits on file access and sharing on the iPad make it really hard to do anything significant.
I considered upgrading my very old laptop, but then I'd also want to upgrade my iPad - so simple solution seemed to be get a Surface: laptop and tablet in one.
The model I got is a Pro 4, Core i7, 8MB memory 256GB disk - and it's brilliant.
Type cover is as good as most laptop keyboards I've used, and has all the keys in the right layout unlike all the bluetooth iPad keyboards I've seen.
Speed is what you would expect of a Core i7 and an SSD - basically very quick, no lag on doing anything that I can see. Of course I'll try to keep it light on servers and background crap that run on my main PC.
Pen is OK, but I don't really use it much - the writing recognition is amazing (even with my dreadful scrawl), but I can simply type faster than I can write, and the keyboard + built-in full width stand is really comfortable on my knee because the whole thing is so light.
And the screen - wow, the text looks like it's been laser printed. In fact it's so clear it looks kind of "big" - I keep checking the font size against other screens and it's comparable, but the clarity makes it stand out, even in paler colours that some people seem fond of using in emails.
So my conclusion is that it's the best laptop I've owned by some margin (unbeatably light, easily powerful enough), and almost as good as an iPad as a tablet.