Polymer ar lowers

[paratroop]

Not really a gunsmithing question, but I know the pros hang out here, and I'd rather listen to your opinions than the animals of general gun and off topic.

I have six "ar15" uppers, that I'm finally getting around to get them thier own lowers. I have one aluminum lower, 3 polymer80 lowers to finish, and one stripped polymer lower(don't remember the make, it is down in the basement somewhere) I'm deciding on the last lower, if it's going to be a cheapo regular one, or a fancy billet deal.

All different caliber uppers.

One is a dedicated 22(that will get a plastic lower, no doubt about it)

One is a 450 bushmaster(that'll get a real lower, no doubt about it)

Then I have a 9mm, leaning toward plastic

7 62x39, 350 legend, and a regular .223.

Is there any recommendations as to which should get the plastic vs aluminum? Or do yall think polymer is garbage, and I'd be better off getting some real lowers?

I also have a 5.7, and a 5.45 upper that could supply thier aluminum lowers for the bigger guys if that makes sense?

I'd like to use was I got, however I'd rather have some of yalls input .

The 450 and 350 are just hunting guns, .22 also, the rest just target shooting.

[kcstott]

I'm no help, I've not seen a polymer lower that I would have any confidence in.

[Ora Serrata]

I’ve got a NFA polymer lower using it with a 223 wylde upper for years. No problems after the initial build which did require some dremel work.

[Oldmandan]

I have a couple, no issues with them.

The broken/cracked ones you see online are all the same brand.

[sigstroker]

I have a couple, no issues with them.

The broken/cracked ones you see online are all the same brand.

What's the brand?

[Oldmandan]

All the broken ones I've seen are Plum Crazy's. Every time a post like this comes up on the web, someone will post the same pics of the same broken receivers over and over again. Makes me wonder how many actually broke? Was it 5000, or 3 that had 5000 pics shared all over the internet.

Anyway, I think the company that made those has been out of business for a long time.

[Disconscious]

I think the main part you need to be particularly careful with is the bolt catch pin on polymer lowers because it has a tendency of breaking. I used a dremel to take some material off of the pin so it fits more easily without hammering it in.

[paratroop]

Plum crazy! That's a name I haven't heard in a long time!

I think im not going to overthink this. My go to rifles are already built, the remaining ones will seriously not see too much range time, honestly after sighting in, maybe no range time!(yall know how that is!)

Thanks!

[Q]

[Q]

Price of uppers
New MGI upper no bcg or barrel $500
Dpms 300 barrel $60 Bushmaster 450 barrel $75
Used LMT monolithic upper complete $500
Used Drd upper complete $600

[sigstroker]

KE Arms seems to have been diligent about testing their lowers. The price is also good considering the lower, buffer tube, and buttstock are all one piece. I think they also sell a finned kali version.