A word of caution about these files. They're identical to the ones I found on Google 3D Warehouse and when opened with Pep Designer, there will be lots of open edges but those are the ones that are immediately visible. Many of the parts are simply pushed in and not melded together. They make look solid and continuous but if you look inside the models, you will immediately see those hidden parts that must be edited out and melded to get rid of the open edges. I tried doing some editing with the gravity hammer but I have since put it in the back burner.
As for the spartan laser in the group, I worked on the same exact model before and it's no better than the gravity hammer, which is a shame because this one was made by RaFaEl and it really looks good, albeit with the wrong proportions. I have already unfolded a spartan laser modeled by Nugget. You can find it in his Halo weapons: 3d Models thread or you can get it below:
http://www.4shared.com/file/38513771/ae8b6..._by_Nugget.html