I've been using an APS 2000 for over a year now. Totally no problems. It has never stopped unless I turned it off. I haven't had trapped air in it at any stage and I am using the original pipes/hoses. I've replaced the floss with 2 coarse and 2 fine sponges on top of the other bio noodles/balls and extra bio balls, all 4 baskets are filled to the top and I have never had flow reduction or issues and I don't go mad cleaning filters that often either.
I don't really understand what the issues with the baskets are. I find them totally fine and can take them out as easy as I like. I don't use the spraybar at all. I think it does reduce the flow. I don't know whether it's due to the narrower section of the outlet connection. It's possible that replacing with the right size 18mm ID spraybar it may work better. I don't know what one means by the pipes kinking easily. Neither the hose or the pipes kink easily.
There's no problem priming it or taking the air out after cleaning. In fact, it's a breeze compared to 2nd hand Eheim I have which I am dreading opening again. And I totally dislike the Eheim green pipes so had to replace these. The APS filter should never be filled with water to the top, just a bit below the top basket. It takes one or two pushes down, plug it in and it primes itself then as long as you haven't filled it to the top which is the reason some people have problems priming these. It may take slightly more pushes the first ever time, but never afterwards.
So this is my opinion, totally different than most others but the same applies to other brand filters users.
I bought a second APS 2000 a month ago for another tank and I can tell they've improved the fit of the inlet and outlet pipes because it took a bit to push them together, so they aren't as flimsy anymore but that has never made a problem with the first filter. From what I've found out by researching, initially the APS's had some major design fault which was soon corrected, but some of the old batch was still being sold around by 3rd party to unsuspecting customers.
You can have issues with any filter or brand you buy. Eheim filters are just better marketed than others and people get convinced they are the best, but if you research more you'll find out numerous "known" issues with leakng and Eheim, even the "new" ones. Tetratecs the same, especially common with the x1200. Both manufacturers produced improved parts in the later production, sending replacement parts free of charge to complaining customers, etc.. The JBL are getting a reputation of reducing the flow a lot after a few months as well. So it's a hard and personal choice what to get.