I am a professional auto technician- I was absolutely thrilled when I purchased the Autel MV-400 videoscope (I got both  the 5.5mm & 8.5mm imagers). Here was a product that had fairly good video quality, good features, & a great price. (The 5.5mm imager has pretty weak lighting- making it not useful unless you are closer than 50-75 mm from your "target".)

The one thing that I would want to improve this product is to have an imager head (8.5mm) that has a fixed right angle - 90 degree side view. Such a device would be extremely useful for inspecting things such as valves inside the engine's combustion chamber. Current 90 degrees mirror attachments are terrible. It is impossible to keep the mirror completely clean - which results in poor visual clarity (it's like you are looking through an ice cube). A fixed side view imager should be fairly inexpensive to design & produce (it doesn't have have to be fancy like snap-on's "dual view" imager on the BK6500 or BK8000).

thanks