AD407/Pro has a 30mm metal lens with a thread for which you can buy accessory lenses (Xit XT30WAB 30mm 0.43X). As for the size of the screen, 7" is quite sufficient. All tripods of these microscopes are not suitable for viewing large plates, because they are blocked by the adjustable column. You either have to use them the other way round or make your own, e.g. on the basis of a telescopic monitor holder.
A lot of people use electronic microscopes and look from the monitor, it is an individual matter. It definitely takes some getting used to in the beginning. See, for example, https://www.youtube.com/@NorthridgeFix or https://www.youtube.com/@StezStixFix
I mainly use them to record close-ups for movies, because they are handy. The most pleasant is in my opinion the good old AD407. The tripod still needs to be modified by yourself. AD407 feeds the image on the monitor and HDMI simultaneously. The 249S-M turns off the monitor when connected to HDMI.
A lot of people use electronic microscopes and look from the monitor, it is an individual matter. It definitely takes some getting used to in the beginning. See, for example, https://www.youtube.com/@NorthridgeFix or https://www.youtube.com/@StezStixFix
I mainly use them to record close-ups for movies, because they are handy. The most pleasant is in my opinion the good old AD407. The tripod still needs to be modified by yourself. AD407 feeds the image on the monitor and HDMI simultaneously. The 249S-M turns off the monitor when connected to HDMI.