For sure the drops can work OK. Even easier are good 4-colour test strips but they are still only good for 0.5 accuracy which is good enough unless you are 0.5 too high or too low.
If you're growing organically and have your soil built with the proper things and know the water quality you really shouldn't even have to worry about pH. With a healthy micro-herd and the right goodies in the soil the pH is moderated by the plant. The roots excrete chemicals to change the pH in the area around it to best get the elements it needs to stay healthy. Also to feed sugars to the wee beasties that are busy turning organic matter into the salts that your plants actually eat. Like when your wife is pregnant and craves cookie dough ice cream with a half pound of real bacon bits stirred in. There's a real reason for things like that believe it or not.
pH pens are delicate scientific instruments and don't take kindly to physical abuse like dropping. With my arthritis I'm prone to dropping things like my camera when angling for a good bud shot while holding a branch out of the way so wrap that wrist strap on any time I'm shooting one handed. Only a $100, 20.1mp digi cam but takes great shots and has manual white balance so I can take shots under any light and the colours are true. The Nikon CoolPix L32. The last of it's kind and the only one that still took AA batteries. My older 10mp L20 had an LCD malfunction from being dropped so much.

Once into a tub of hydro nutes tho still worked for at least two years after that mishap and I did have the damn wrist strap on tho was so close to the surface of the nutes is went full in with the lens extended. I even opened up the back of the camera after and flushed it out with RO water to remove all the salts. That one cost over $400 when I bought it but it worked for 7 years or so.