I want a gun with a light bcg. I've seen some say they need an adjustable gas block others dont. Whats your opinion or experience in the current year?

Nice. What gas length?

I like the the adjustable but I've run a couple SLR which is considered the best and after a few hundred rounds they become un adjustable with build up. This has been my experience with all brands I will go with SLR if I need to because if you complain they will probably throw you a free one, excellent service.

I will break down an upper if it has bad gas problems before I put a adjustable on a build anymore.

Yes, but with a Spring CO Blue or Wolff XP spring.

In my 3 Gun AR I ran a JP LMOS with an Odin Works adjustable gas block, and Tac Com reduced recoil spring.

I did, didn't like it, I wouldn't recommend it. Biggest problem is the extraction process speeds up. You can slow it down by increasing the spring rate but the amount required to properly delay unlock Is excessive and in my opinion far from ideal. It does work for the most part.  When reducing bcg and buffer weight you would ideally increase spring rate and decrease gas flow. If you do not wish to change your gas block then look into adding an adjustable gas key to the lightweight carrier. I have an RCA key on my aim lw bcg with a strike industries flat wire spring. I also have a rifle with a 2A regulated bolt carrier that has adjustable gas built in. Works great.

I'd used a lightweight carrier in a gun with a Faxon 20" gunner barrel (rifle length gas) and it ran just fine with a very smooth recoil impulse.  The same goes for an 18" intermediate gas rifle I have.

Both guns use carbine weight buffers.

Same here, but with a rifle lower and carbine gas.

Thanks for the replys. Think I will tryba regular block and break the upper down if it doesnt work

Or could I just use a adjustable gas key? I can say I've never even considered one before, are they as reliable as an adjustable block I wonder

I run one on a .300bo 8.5" upper, but that's under gassed with subs and would not cycle an FA BCG.

With an AIM Surplus lightweight BCG it cycles subs with a std. buffer & Sprinco yellow spring and for supers I swap in an H2 & std. spring.

My preference is a slow & heavy BCG, seems to work best with all my variant calibers that had issues running a standard setup. Seems to smooth out the felt recoil impulse.