Well, the gloss does sit kind of heavily on the eye. That's its main disadvantage, along with the fact you're not going to get more than 4 hours of wear before the full effect is gone. If you don't mind the way lashes feel heavy on the eye, then the gloss won't be an issue, since it's not as heavy feeling as lashes. I'm not sure how the lash glue will interact with the gloss, since I almost never wear lashes. I'd probably put the lashes on first, then the gloss, then liner, if used.
I think the gloss looks best on eyes without liner and very natural mascara, although it also looks great if you use a very natural brownish liner like Our Secret to add a little depth, and some contouring in the crease and around the outer part of the lid - I've done that and have been very happy with the results.
I only mentioned it because I found the most perfect flirty natural lashes at sephora today that just simply make me look like I was blessed with nice eyelashes. They're really nothing too bold, so I was thinking maybe I'll pair them with the eyegloss since I'm a fan of bare lids and flirty lashes like I'm wearing today. Glossy lid and flirty lashes sounds gorge to me right now but maybe youre right, I'll see how I like it when I'm able to buy the eyegloss. Thats a good idea to do the lashes first though, dont know why I didn't think of that, hahah.
Now that I re-read your original post, BLURPLE? omg I somehow missed that, heading over to that thread right now!