Looking at one of these: https://store-z1t759.mybigcommerce.com/ar-15-style-lightweight-color-lower/

Both for lighter weight, and budget reasons.

Anyone dealt with them?

By the time you pay a transfer fee, why not go with Aluminum?
I have one polymer lower by another company. I got it super cheap, but wouldn’t go that route again.

I have a handful of their AR-308 lowers which I got on a good clearance sale (apparently purple color didn't sell well) for $40 each with a 15% off coupon when they were also running a free shipping on $100+ orders sale back in the Trump Slump days when components we're plentiful and cheap.

They as a company seemed fine to deal with and they shipped my order out to my local FFL in short order and everything was cool for that even though I basically robbed them by stacking a clearance sale, coupon code, and free shipping sale altogether in a mean sandwich like that on them when all the stars aligned just right.

As a lower, they are polymer and are not suitable for pistol builds.  You need to build them with shoulder stocks and tuck the stock into your shoulder and not do a bunch of hip shooting.  Do that and don't use your gun as a club or pushup bar or abuse it and they will hold up.  Mine have done well even in cold Sub-Zero winter weather.  I was surprised they didn't get brittle so they are using a decent polymer.

It is true though that their AR-308 lowers have s better reputation and are known to hold up better then their AR-15 lowers and my experience is based on the large frame where you are considering the standard frame.

Even then of course I consider mine to be a consumable item and I don't expect them to hold up forever.  Just let me build a lower for every DPMS-308 pattern upper I had without having to pay $170+ for stripped lowers since the larger frame lowers are usually so much more expensive.

For a AR-15 standard frame polymer lower I would actually stear you to this: https://www.brownells.com/rifle-parts/receiver-parts/receivers/lower-receivers/kp-15-stripped-lower-receiver-polymer-black-sku100036999-132660-243460.aspx

That is the only polymer AR-15 lower that truly is a long term fully capable solution.

The lowers are decent and I know several people who bought and built rifles from them. I've seen the same problem on two of the lowers. Each had the detent hole wallow out above the selector. We drilled it and put a hollow rod of a similar inside diameter as a fix. I recommend anyone building one to trim the selector detent spring by enough so there is little resistance to switching from safe to fire. That should keep the detent from stressing the plastic hole. Other than that one flaw the rifles go bang.

Poly is fine......for a 22LR.  Get the real deal if building anything else.

I have several AR 15 lowers and they are good lowers.  They won't replace aluminum but they are cheaper.  I have one mounted on a 16" carbine upper and it makes for a nice light weight rifle.  I have another completed lower but I don't have an barrel mounted on the upper I currently have on it.  Maybe when ammo and barrels get more affordable I'll finish that upper.  I was thinking about doing a light weight 6.8 spc.  I also have one 308 lower and 2 9mm lowers but I have not completed them so I can't really comment on their durability or build ability.

kwg