Really like your entry 31. Could this work in lime green (see brief for pantone), also think very clever to have the IS combined and reversed in the logo but wonder if the proportions on this could be more balanced with the text. i.e. shorter fatter logo next to a lower case 'integer solutions'
Ok I have been thinking more and wonder if the logo can be on the same level as the font (though slightly fatter) and that the text could be larger to balance it out more. also in green would be great if you feel up for the challenge.