Since this is primarily a painting forum I have to rate this a 6. I like your conversion but I must fault it for bending upwards in such a large way. Please don't be discouraged by me saying that, keep up the good work and creative thinking and if you see a conversion is lacking something (I'm sure you noticed that the gun was bent) don't paint it - unless the error is simply beyond your capacity to execute correctly (sculpting eyelashes etc). I do like this piece as a whole however, which is what's important.
Simple but cool conversion, paintjob is tabletop. I think it's great to see someone paying some attention to the Grotz. I'm even thinking about doing an entire Grot army.