I'm working on building a SOPMOD styled M4 based on the older Block I. I won't have every component an exact copy of the original, but I will use kit that I find in my styles of gameplay to be very useful. I'll list off what I intend to use, then the weapons I want to use and why. This would technically be my first good quality AEG, so I want to make a good enough decision and have room for what I want to add to it. If there is an option that is good, but I didn't list, please let me know. So far, I realize I'd use the following attachments: NcStar Aimpont replica, mounted on a cantilever mount Replica ACOG (red/green dot non zoom variant) AR15 styled scope (carry handle/weaver rail mounted) RIS unit, non free-float Vertical foregrip M203 Older (XM177E2) stock MOE stock MOE handguard MOE vertical grip Barrel extension (tracer/non tracer) M4's I see possible to use: Classic Army M15A4 Sportline G&G Combat Machine ICS M4 Sportline JG M4 Enhanced* JG M733C** Elite Force M4 King Arms M4 *Using JG as a last resort. Would really like to avoid using a M4 that didn't come with a real rifle styled delta ring, but since it does come as with an aftermarket part, I'll manage. **With the M733C, I'd be able to switch from late Cold War to present times. More money goes into having a separate receiver, but then I could do a BHD loadout. I could always do that kit separate, but still could be an option. I've spent quite sometime researching this topic. I'm not trying to sound like an expert, because I know I'm not, but I did put forth some effort in figuring out what to do. Again any help, tips, advice when going into this build after picking the weapon would be helpful.