Tacoma,
'Need' implies something would go wrong or won't work if you don't have it. Those situations are possible and you won't know until you start shooting whether this is you. Beyond that however an adjustable gas block gives you control over how the system works. That's good for a bunch of reasons, including longevity of parts, suppressors, recoil management and how that effects accuracy. The downside is the reputable ones cost more and they are made of moving parts (only a couple). I screw mine closed and open again after every shooting session and that seems to keeps it from seizing up.
From another perspective, this is your gun and not the tax-payers. If it were then fixed blocks are the norm and if things break because of it you just get given a new one. Fewer working parts for a thousand ham-fisted idiots but this cheap simplicity comes at the expense of fine-tuning.
I say you are better off with one than without one, unless you actually need one and then you have no choice.
'Need' implies something would go wrong or won't work if you don't have it. Those situations are possible and you won't know until you start shooting whether this is you. Beyond that however an adjustable gas block gives you control over how the system works. That's good for a bunch of reasons, including longevity of parts, suppressors, recoil management and how that effects accuracy. The downside is the reputable ones cost more and they are made of moving parts (only a couple). I screw mine closed and open again after every shooting session and that seems to keeps it from seizing up.
From another perspective, this is your gun and not the tax-payers. If it were then fixed blocks are the norm and if things break because of it you just get given a new one. Fewer working parts for a thousand ham-fisted idiots but this cheap simplicity comes at the expense of fine-tuning.
I say you are better off with one than without one, unless you actually need one and then you have no choice.