Hey team! Chris Chapman here. I was the sport scientist for PUSH that worked with Brett Jones and the team to bring PUSH to strongfirst. It's very unfortunate, and also devastating for me and the team personally, that PUSH was discontinued after the acquisition. 8 years of our heart, sweat and tears gone overnight.
I came across this post as I still comb the internet for VBT stuff regularly. Since I have zero bias to any devices anymore - i'm happy to give my two sense. You are pretty much limited to IMU style (intertial motion units - output, vmaxpro, movefactor X, calibrex) or camera phone based systems (metric, true rep, and others I need to do an updated review).
For the IMU's, I would have said output was the closest thing to PUSH, but the price is definitely more prohibitive. Also my colleague who worked with me at PUSH is just leaving them, not sure it will be a long term solution and may run into the same issues as PUSH. The other devices I haven't tested with KB exercises (we worked with Stongfirst to dial in the algorithms for all the exercises within their training model). Calibrex is the new kid on the block, and knowing how long it takes to dial in valid algorithms my guess is they will be more like beast at this time from a validity and reliability standpoint. We also found the magnets could fly off the KB depending on the exercises (this was with beast) so it is a potential problem with any magnet device. We were going to create a magnet attachment but decided against it. Movefactor X will be the most affordable option in this category and I know the creator Scott Damman has put a lot of resources into measuring power.
As far as the phone camera systems, to me the have a bit more friction. True rep intigues me the most I haven't used it. There is a little green magnet you put on an implement and then use your phone. I don't think they have KB exercises yet but would be interesting when they add it. I see this style of measurment becoming the norm but they have to create a UX/UI that is frictionless. This was one thing we put above all at PUSH was usability.
The string pod units aren't really an option in my opinion. They are great for barbell work but would be annoying for KB work. Also many of them don't have an angle sensor so as soon as the string isn't vertical the accuracy is off. Some do have angle sensors but dealing with a string isn't an option for Strongfirst style training.
I'm going to do some homework and try to answer this question as i'm curious for my own purposes. I use Q&D protocols a lot in my training and coaching and also need a replacement. PUSH still works at the moment if you have the app and don't need to update it but I know this will be short lived and not a long term solution. I know some are having issues with the app and can't get it to work.
If anyone has any specific questions or things they want me to look into as I dig into this further let me know! I'm going to stew on this more for sure.
