Drum Booth advise

Hi. First let me just say I am new to this board and I am very thankful to be a member. I have learned a lot reading tons of threads on this forum and cannot be more grateful. Okay. On with my questions. I will be building a drum booth in my backyard as I don't have the space anywhere else. I will be building a mass-spring-mass type walls. Spring probably 3". I was going to use sheetrok to sandwich between my plaster boards but Auralex prices for this stuff is just insane and was told that for what little it does for the price I don't need it. Is that true? I was also looking into this stuff http://www.rockwool.co.uk/sw59344.asp or this stuff http://customaudiodesigns.co.uk/soundproofing/amw.htm to put in between my studs. Mainly because once again it's cheaper than Auralex. Are either of these products any good for sound insulation for a drum kit? My final question is regarding the RC Channels. I have heard conflicting things about these saying there is only one correct RC Channel to buy. Is this true? If so what is the right one? Sorry for all the questions but I live in the UK and a lot of this stuff is either hard to find or impossible. I have come across a couple of companies that do there own versions of these materials mentioned but there either called something different or the specs are completely different. The whole metric system and all. Gets confusing. Once again my apologies for going on and on. I just want to get the right materials for the job and not buy a bunch of shit I don't necessarily need but If "doing it right" and quality justifies the expense then I'm okay with that but if anyone knows of any cheaper options for the materials I need, please lend me some kind advise. Thanks in advance. Kevin Location UK Room Size 6 feet by 9 feet by 8 feet Tall For isolating heavy rock drums. Build will take place on roof top terrace. Floor WILL hold. Neighbors below and Also one next door. Hopefully I haven't forgot anything. Apologies if I have.

Okay after doing a bit more research I am going to get rockwool instead of the "Fluffy Stuff" for fire safety. I'm not going to bother with MLV or sheetrok whatever you want to call it. The only thing I need help finding in the UK is the correct RC Channels. I'm getting desperate now as I want to get on with my build. There is so much stuff on forums that are so conflicting regarding these that my head is starting to hurt. Do I really need them? If yes, where in the UK can I get them? Please help.

The insulation placed in between the walls is there to damp the cavity, stop it from making it's on sound. So insulation is all you need there, nothing special. As for RC, you do not require it at all in a build that will have double wall construction.

Thanks for the advice xspace. I been reading up about that also. Unfortunately I couldn't find any good info on this until after I posted this tread. Thanks again for the advise.

Hopefully what I posted and what you read agree with each other ;)