I have the Asus TF700, Nexus 7, iPad 3 and mini, and the N10. I never realized that the N10 doesn't have a SD slot. I guess that's not very important to me on that device. I like the speed and display, and I use it for basic schematic capture and electronic simulation - the display makes it quite good for that. It's funny how the selection of simulation apps is better on Android than iPad,while iPad has much better drawing apps. I wish they'd either get some sim apps on the iPad or some good drawing apps on Android. But as for regrets? No. The N10 is a wonderful tool. It is the only pad I've found with decent sound, so when I'm on the road - and I get good wifi, which is really iffy in motels - I can watch movies. It is a good substitute for a laptop as far as apps are concerned and in my narrow range of use - although despite the bloggers wailing about the post-PC era, I don't see anything taking the place of my computer when I actually need to sit and work for more than 20 minutes.
However, truth to tell is that there are a crap-ton of good 10" tabs out there. Asus is leading the pack right now, but Samsung is doing a good job - I find their Note tempting. Apple is better in some ways in terms of apps, and I like their display aspect ratio better than anything in Android. I wish there was a maker who would adopt that ratio. If I were you I'd look at the stores for apps, then base my decision on that.
However, truth to tell is that there are a crap-ton of good 10" tabs out there. Asus is leading the pack right now, but Samsung is doing a good job - I find their Note tempting. Apple is better in some ways in terms of apps, and I like their display aspect ratio better than anything in Android. I wish there was a maker who would adopt that ratio. If I were you I'd look at the stores for apps, then base my decision on that.