Yes I agree with the fact that the simulation is just a rough approximate of the real world performance which is not accommodating for parasitics, and I did state so. The gerber files would be something I’d definitely want to see.
I opened up the scope yesterday and the R and C are definitely smaller than 0805, so I will order the parts I need to tweak the front end soon enough. I am planning on running a frequency sweep on the front end only and monitoring with my Tektronix - this way i won’t be limited by any firmware / software faults to properly determine what are its actual capabilities.
As far as slight overshoot - C37 is killing AC performance at higher frequencies just like C9, C11, C10 and C12 do. Removing the capacitors opens up the BW so the op-amp will perform closer to its specs which do show slight overshoot at the falling edge on the step response plot. The behavior is slightly worsened probably by parasitics. As bielec pointed out these capacitors were there as an afterthought or maybe even planned as space holders as compensation network which is fine. I have the feeling that the final values placed in our units did not get tested before hand however. In other words some fine tuning needs to be done to get the max benefit from this very simplified front end.
Like bielec I also noticed the triggering problem at 0.1us and 0.2us. Actually the signal fails to reconstruct properly on the screen once I exceed 2.3MHz or so. I will need to rerun all this once the analog BW is opened up.