How reliable are virtual hair-colour previews?

I have a colour consultation booked soon, and I am considering a change from my natural dark blonde. I would like something subtle enough to grow out well, not a dramatic transformation that needs constant maintenance. The reference pictures I saved move between cool-summer ash blonde, and each one seems convincing under different lighting. I tried two browser previews, but the screen often changes the room light. That makes every option look more successful than it might be outside the app. My biggest concern is picking a shade that clashes with my eyebrows. I took one set of pictures beside a window and kept my hair, clothes, and camera settings unchanged. To sort the realistic options, I checked hair colour analysis as a check against impulse choices. I am now leaning toward a muted dark-blonde blend, provided the stylist agrees after seeing my hair in person. I will also ask for photos in daylight. Would a strand test answer more than another set of virtual images?