Used Gleim only so far and it has worked out well. Gleim has a guarantee thing that will grant you continued access until you pass if you complete most of the study material. Of all the stressful things about the CPA, this continued access thing really helped me calm my nerves.
I got a discount through my employer, but I think it was in the $700s for books and online access for all 4 parts. I also liked how quick they were to respond to my inquires about questions I couldn't figure out. I think I've asked around 10 question so far. The amount of info and questions provided by Gleim is substantial and at times overwhelming which is good and bad when you're reviewing everything over the final weeks.
If you do get Gleim, get the lectures. The presenter for FAR was entertaining and definitely helped my understanding for some concepts and how to tackle very wordy MCQs. I didn't have the lectures for the other parts because they didn't exist so I don't know if they are any good.
So far I'd rank Gleim very high on quality of material for AUD and REG and decent for BEC. Gleim BEC came off as a bit easy and the actual exam wasn't, but I was challenged quite a bit in my AUD and REG studies. If I wasn't working full time and didn't have to worry about overtime and meeting deadlines I think I could have exceeded a score of 90 on AUD and REG.
I have the same feeling about FAR and feel Gleim has given me the tools to crush the exam, but will find out tomorrow. The amount of info/questions provided by Gleim for this part is definitely overwhelming and I didn't even come close to seeing every question at least twice which is concerning but think that was mostly due to cramming all of FAR into 7 weeks of study thanks to illnesses.
I have heard from a lot of coworkers that they hated becker and others said they liked it. I frankly thought they were overpriced and went with Gleim since that was the materials I used to pass the CIA exam. I've heard very good things about Roger materials though.