I like the material of the keyboard buttons surface but the depression from the keyboard - the tactile feedback - was disappointing to be honest. Otherwise most of the positives above. To be fair I haven't tried the alternative(s).
This one?There is a clear one from ESR that's on sale over at Amazon for right around $10. I wish I had the link for you and might post it later on, but don't have it right now. I have it on mine and love it.
I am actually surprised how sturdy it seems to be, also I heard that the Zagg Slim book makes the iPad VERY heavy, like Macbook Pro kind of heavy.
This one?
iPad Pro 9.7 inch Case, iPad Pro 9.7 Case, ESR [Perfect Match with Smart Keyboard] Slim Fit Shell Case [Soft TPU Bumper] [Corner Protection] Back Cover for iPad Pro 9.7 inch 2016_Clear https://www.amazon.com/dp/B01D1NUF20/ref=cm_sw_r_cp_api_VoipxbVEY9ESJ
I have no experience with the Smart Keyboard, but I generally shy away from any keyboard case which locks me into one model of iPad (and in this case, one single product).
The keyboard also cannot used to prop your iPad in a 30 degree angle or less, which limits its utility for drawing.
I recently purchased a Logitech keys to go keyboard. It's cheap and thin and light and the typing experience isn't all that bad. I like it a lot.
https://www.amazon.com/gp/aw/d/B00VBNSCM8/ref=oh_aui_i_d_old_o0_img?ie=UTF8&psc=1
How do you see yourself typing? If it's an enclosed or cramped space like a lecture room seat rest, a keyboard case might be the best way to go. If it's a more spacious environment like on a table, an external Bluetooth keyboard should suffice. Then get a cheap case which protects the back and with a Smart Cover that can be folded back as a stand.
Hope this helps.
@mrcb would be wise to heed the opinion of this post.
The worst part of the ASK, IMO, is the price. Once one gets over that, it is the best option (again IMO) for the reasons that @zhenya cite. I too have had many types of keyboards for iPads... including the keyboard dock that Apple made for the iPad 1. They were all adequate for the task but not preferable.
With the ASK, it really does feel like an extension of the iPad, not yet another device that needs to be "cared" for. The 12.9 version is a joy to type on and has replaced the Surface TypeCover as my favorite keyboard for a portable device. The greatest challenge was adjusting my typing position and approach because I no longer had to incorporated a cramped touch-typist position due to a keyboard that is confined to the 9.7 screen size of the iPad.
The value of the ease of removing the ASK cannot be overstated. To go from notebook-y type usage to an unencumbered tablet mode so quickly and easily goes a long way towards a converged/hybrid device.
Was about to buy ASK and noticed it does not have ESC or DEL keys. I used these two keys extensively with my old MS BT keyboard. Excel, Parallel Access, etc.