Best eyelash extension glue to recommend?

I am currently training as a lash technician and am being trained with Marvel glue. I have done my research and found it is not great for lasting results. I have visited the Flirties website as a lot of people have recommended them for fantastic lasting results, but on their site i cannot seem to find the glue only semi permanent black mascara? am i in the right place? Also read up on Lash by Francesca and people have said that it is very fumy! Please reassure me if you find these are great glues or inform me of other glues?
Thank you! xx

I got trained with Marvel Lash too but my trainer told me the glue wasn't good and to try Lashbond which is great but I noticed most people on here talk about Flirties so im thinking of trying that next. I found a website called wowfactorltd.com that sells it. xx