The Chrony line is pure crap. Yes they can be made to work & yes they are accurate. If you only need to check PF for the occasional load, plenty good. The problem is their small poor screens. So buying the more esxpensive unit doesn't fix anything, they all use the same poor screens.
If you use one to develope handloads, then something better like the CED will be easier & less frustrating to use. I am lucky & got an Oehler before they stopped making them. Best screens on the market & w/ any chrono, it's all about the screens for accurate measuring.
"Given adequate penetration, a larger diameter bullet will have an edge in wounding effectiveness. It will damage a blood vessel the smaller projectile barely misses. The larger permanent cavity may lead to faster blood loss. Although such an edge clearly exists, its significance cannot be quantified".