I have no regrets buying my Lumia 2520. I bought my tablet with the power keyboard for a total of $250 so it's easy for me to be happy of my purchase. Honestly, if I bought the tablet for the original price of around $500 and the keyboard cover for $150, I'd be extremely disappointed.
I mean, feel-wise, this tablet and keyboard don't feel how a $650 product should feel. The materials feel good to hold but they feel how my $150 Nexus 7 felt when I first bought it. Furthermore, the keyboard cover feels extremely flimsy, especially how the touch pad just... just flops about when I tilt the tablet backwards on it's stand. I do that, you see, because the fixed angle of the stand is waaaay too vertical for me to use comfortably unless I'm laying down.
Nokia should have come up with a more elegant, built in stand for the tablet itself so that the powered keyboard cover can simply focus on being a more useful powered keyboard cover. Thankfully, the keys themselves feel wonderful and it feels like I'm typing on a slightly downsized version of my Gateway LV's keyboard.
My only issues with the tablet itself besides the lack of a built-in kick stand is that Windows RT won't let me upload a photo for the background (the round-about way of uploading a background in desktop mode works, but I don't always want the same image in desktop and metro mode), I dislike how you can't change the default font size across the entire tablet, and I also dislike how the screen is a fingerprint breeding ground. The keyboard cover circumvents this, of course, but the plastic it uses absorbs finger oils that WILL NOT wipe away if you have better things to do in your life than constantly wipe finger oils from your keyboard.
Again, for the original asking price, I feel that this tablet and keyboad combo makes no sense materials wise and useability wise, but for the price I got for it's awesome as hell. I REALLY hope Windows 10 works on it because I am getting sick of Windows RT's issues (there's more issues that I didn't cover in the post).