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I have this: https://www.amazon.ca/Avantree-Adjustable-Portable-Standing-Breakfast/dp/B01A81FBQS/ref=sr_1_1?ie=UTF8&qid=1508264717&sr=8-1&keywords=avantree+table
I use it alternate between standing, and sitting in virasana or a simple crossed-leg position on the floor.
may be a bit too short???
You're more than welcome, I'm glad to help!
I totally understand your position regarding the K63. As I said, if you already have a good pair of keyboard and mouse, that device isn't worth the investment. I only mentioned it because I thought you were more interested in a true lapboard rather than a "lap desk".
I actually purchased a couple of lap desks in the past, but with my laptop in mind: this one and this one.
The second one is really good for laptops when you're lying in bed or on the couch, but I wouldn't recommend it for kb/m use. As for the first option, it works much better as an actual desk replacement, and there's a larger sized version that could be perfect for you, depending on your intended use.
Are you planning on using that desk while sitting on the couch, like Paul does on the video I linked? Then I can vouch for it. If you're thinking about using it while lying down, however, that desk is still too "tall" and uncomfortable to use, even at its lowest height setting.
The one you linked also looks like a nice option, but I'm concerned about those legs - they look rather flimsy. If you're going to support it on a solid base, like a coffee table, it probably won't be an issue. But if you're actually balancing the table on the sofa's cushions, then I'd suggest going for something a little more robust.