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While it is harder to compare as there is a chip generation between them, I find my ASI2600 (16 bit and approx 50Ke full well at lowest gain) to be a far nicer camera that produces much "smoother" images than my ASI294 which has 64Ke well depth at the lowest gain but at the most equivalent gain conversion wise to the 2600 has only about 16Ke effective full well due to the 14 bit architecture, that 16K ADU is then multiplied to fill the FITS 16 bit frame. There was plenty of debate about it while I was waiting for the ASI2600 to arrive, but the 2600 is unarguably just a better camera than the 294 was.
Even when read noise differences are taken in to account, at their most comparable and useful gain settings (120 for the ASI294 and 0 for the 2600, the closest each camera has to 1:1 conversion) you see about 1.8e read noise for the ASI294 and 3.6 for the 2600, the new camera has almost twice the dynamic range as it can encode up to approx 50Ke where the ASI294 can only run to 16Ke at that gain. The practical difference is that on dimmer targets the 2600 responds well to 600 second subs where the 14 bit 294 just turned into a mess with increased saturated stars, and while the 2600 at that lowest gain has approx double the read noise of the 294 at the equivalent gain conversion wise, it does not look it.
Each to their own and budget might be what answers the question, but I don't plan to buy another camera where the bit depth does not allow for near or actual 1:1 conversion at a truly useful gain setting, not for deep sky imaging anyway.
To touch on the point Dunk has made about learning to get the best of it. That is one of the surprises with the ASI2600, getting really good results out of that has been a matter of plugging it in, shooting darks and then just using it, even flats are really easy to get and apply. I am sure it is not the only camera like that on the market but my ASI294 as a comparison takes a lot more work in terms of getting flats to actually work well, and even than only up to a point. I stopped trying to go after targets on a dark background as it was just too much work to try to get them looking nice where the ASI2600 on the witches head for instance was just "wow, look at that" after 21 subs, with the ASI294 (I am still using it) I aim for 100+ for a similar looking result but even then the flat framing issue would rear it's head.
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