A little while back I criticised Pebeo as the fluid got on my trousers you can't get it off. My fault actually and Pebeo is well liked and used by several of my painting friends. Be wary though it's dreadful stuff to remove as are other makes of masking fluid, but then acrylic paint is nearly as bad and some of the more recent synthetic watercolours are heavily staining and also hard to remove.
Above are the Pebeo tubes, still in their packets. The concept is similar to Molotow except the Pebeo sizes are 04 and 07. I haven't tried them yet but those who have amongst my painting group who have tried the Molotow system are not impressed. The complaint is that the fluid is hard to remove and damages the paper, especially if the paper is on the soft side. I have not had such an adverse effect so far but I can see why there is a problem if you leave the fluid on too long before trying to remove it. Also in the photo above is the 'Maskaway', according to the blurb a sort of hard rubber that makes it easier to remove masking fluid. Again not tried it yet. I got the above from the SAA (Society of All Artists) where we as an art group have an associate membership. The SAA claims to be a Society but is more like a large scale web selling operation with a comprehensive website and catalogues.
My friend John Softly prefers the Daniel Smith system of interchangeable plastic tubes, that vary in size. I've tried them and also the Masquepen system but found problems with all. Some of my friends prefer the Masquepen system.My problem is the cleaning of the fluid from the tubes. Maybe it's just me. I think I'll go back to using Pebeo with a ruling pen.