I use an inertia switch and a battery pack with my LabRader. I don't miss any shots unless I don't arm it. No aiming problems, no triggering problems, have never picked up someone else's shot. The menu layout isn't the best but after a year of use it's intuitive enough. I use a high quality camera tripod under it and it's been more than stable enough.
I chrony every shot I take at the range now. There's no reason not to, it only takes 5 minutes to set the LR up. If you really want top get serious about ES/SD you need to increase sample sizes. Oh look at my 5 shot ES of 8! I'm a master reloader! Start catching 40-50 shots in a row and you'll you'll think the sun sets out of your behind when you get an SD of 8 and you'll want to cut someone for commenting on your ES of 35.
Consistent muzzle velocity is key for long-range shooting, otherwise, bullets that leave the muzzle...
precisionrifleblog.com