Keep in mind that I've only ever used tiles before trying this, and I haven't had much time to get acclimated to using it yet.
PROS: The product description said that it would fit 3 rows, but I fit 4 on it easily (I like to do a more subtle gradient on some clients), and I'm pretty sure you could fit 5 if you wanted.
The curved surface was great for fanning the lashes out making one easier to grab than on the flat tiles.
Getting from lash pickup to glue was streamlined which did make that part of the lash application faster.
Cleans easily and still looks good. (I hate that some things you use over and over start to look a little worse for wear from the actual products used to kill bacteria and germs on them).
CONS: I think this ring is better-suited for someone whose mastered isolating with just the left hand. I'm still most comfortable with the original method I learned with (isolation w/ both tweezers, lash pickup, glue, place... as opposed to lash, glue, isolation w/ non-dominant tweezers, place). After isolating and holding with the left hand I usually had to adjust my hand position to access the lash I was going to place which frequently meant losing my isolated lash.
I was also nervous about pouring the ring's glue on my client the whole time (although that incident didn't become a reality). I think using it exclusively on my non-dominant thumb and only using 1 drop of glue at a time would help with that.
Overall, I'm glad that I purchased this. I can't say that I'm totally comfortable using it yet but it's pushing me to get better at one-hand isolation. I do think it's going to cut my service time down eventually..