The Instant Pot has been the best selling multi-cooker at Amazon, and that is for a very good reason: you can cook your meals 2-6 times faster. Imagine making pot roast or kalbi jjim (Korean braised beef short ribs) or chicken stock in under an hour instead of 4-5 hours. Or 15 minute risotto. While the highlight of the Instant Pot is the pressure cooking, it can do so much more: saute, steam, slow cook, and many program modes such as yogurt, poultry, and porridge. The Instant Pot product line includes LUX, DUO, DUO PLUS, ULTRA, and SMART. See full product line comparison here. My recommendation is the DUO.
Why the DUO is better than the LUX:
DUO can do everything that the LUX can do plus it can make yogurt.
DUO’s lid is much nicer. The DUO lid handle feels very secure whereas the LUX lid handle is like a mitten that you have to slide your hand into and a little awkward. Also, on the DUO, there are slots on the handles of the base unit. You can insert the lid’s handle into that slot so that you don’t have to put it down on the counter top. See picture below.
DUO has a larger LCD screen. I’m getting old, and my eyes aren’t as good as they used to be.
DUO’s Keep Warm setting can go up to 99 hours vs. 10 hours on the LUX. I don’t think this will be a big issue as you’ll probably finish all your food or refrigerate it, but this might be important to some.
DUO has both high and low pressure settings while the LUX only has a high pressure setting. You will most likely never use the low setting as 99% of all pressure cooking recipes are for the high setting. But from what I hear, you can make perfect eggs on the low setting.
Comparing the DUO to the more expensive models, in a nutshell:
The DUO PLUS adds Cake and Egg modes.
The ULTRA also has Cake and Egg modes and adds temperature control so that you can cook sous vide.
The SMART is basically a DUO with bluetooth connection so you can monitor using an app.