I am far from an expert on this topic, but I know some decent advice.
I bought the BOS-2000-2. I did a minimal amount of research. Looked at several different review pages that seemed somewhat trustworthy. It was recommended as an option. One reason I bought is because it's battery powered and personally I assumed pumping it manually would be a hassle. Another reason I bought it is because it was not cheap. The product works well for me and I think it's well-made.
I've also heard from several people who would have some experience on this topic that a LeVuv from ebay is a good option. You can get a lot of different sizes cylinders, and I think that's important. Make sure you learn and understand what size cylinders you will need. I can't tell you how to do that, cause I didn't know I needed to do it, and it's been a pain lol.
And if you or others have not seen it, I wrote my opinion on the importance of using a VED before and after implant if you wish to regain or increase size. But my opinion is also supported by evidence from research studies:
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40. AMS 700 LGX, 21+3. Nov. 2, '21. Replaced Titan 28cm, Jan. 14, '25
Proved implants increase dick sizeAbused alcohol for brain injury, abused viagra for implant
Pre-op size: 8.75" x 5.7"
Current: smaller
Goal: 10" x 6"+