870 hd questions

[SamDBL]

I used to have an 870p that I loved, but never shot. I sold it and got an he express instead. Even though it suits me just as well, I kinda of lose a little sleep over the loss of perceived durability I had (ie, the 'cool' factor) I lost by downgrading to an express. I am still kind of confused at the lines rem offers. It seems that wingmasters are geared towards hunting, and the couple of 870p models are specifically for police. But the 'normal Joe' civilian ones (majority of their offerings) are express models. Aka, the cheapie budget models. It's odd to me that the civilian line, which obviously makes up most of their catalog, is also the budget line. Seems like there is quite a gap in their lines. Either you get the special police model, or you get the cheap o Wal-Mart model.
I was happy to see that this model (bought new, but serial number indicates 2004 build) does not have the huge for end that I thought all the express models had. In fact, except for the sights, this one looks the exact same as my dearly departed police model. It also doesn't say 'express' on the side.
Anyway, I upgraded to a non mim extractor. What are the other parts I need to buy to make this a super durable gun? I'm not looking for super tactical, so not so interested in stocks, lights, extensions, etc. I am also ok with the plastic trigger assembly. More like what would make this a some, yet extremely durable and reliable weapon that would compete with the 870p. I think I'm mainly looking at springs. A simple list with links to where to buy would be super appreciated. I plan on getting it refinished, so that's not a problem. I know there are springs, but I dont know which ones. I know the follower as well. I see the brownell stainless one recommended. But what about the slightly cheaper aluminum ones for sale on Amazon?

[Synchronizor]

Expresses, Wingmasters, Police models - all 870s are the same guns that use the same design and function the same way. Nearly all parts differences are due to differences in intended application - a civilian 870 built for hunting or clay sports will obviously have several differences compared to a Police model built for combat, and that's what tends to confuse things. Where money is saved on the Express models, it's done with secondary things like a more basic finish, or furniture that's not as pretty. The barrels, receivers, and other structural or functional parts of all three guns are built just as strong, and mechanically, they're essentially identical.

For details on what differences there are, you can read through this post comparing similarly-equipped Express & Police 870s.

Think of the different 870 lines like trim levels on a car. The Wingmaster is the luxury trim with leather seats, a fancy radiator grille, flashy rims, and metal-flake paint. The Police is the utility trim with extra undercoating, 3-layer protective clearcoat, and maybe some useful extras like fog lights or a trailer hitch. The Express is the base model; fabric seats, basic paint, plastic hubcaps, etc. But with all three, you get the same engine, transmission, suspension, tires - all the stuff that really matters in a car that'll get you from A to B reliably for decades. The higher-end trims may have some nice features, or be more resistant to the elements if you don't keep them in the garage, but they're not tougher or better-performing.

I know the follower as well. I see the brownell stainless one recommended. But what about the slightly cheaper aluminum ones for sale on Amazon?

For the record, the factory plastic followers work fine and stand up to heavy use admirably (the same part is used in all 12ga 870s), but there are a couple nice added features that aftermarket followers can provide, like being able to tell by touch when the magazine is empty. If you want to change out the follower, I recommend going with one of the high-end polymer options (like those from S&J Hardware) over the metal alternatives. Aluminum followers can deform and become unreliable from repeated impacts against the receiver's steel follower stop, and the same impacts with steel followers can actually damage the receiver. Admittedly, it takes fairly heavy use to see either problem, but I still consider a quality polymer follower to be superior.

[SamDBL]

That is kind of what I figured.
So I'm considering small upgrades. I doubt I will get carried away with things like metal trigger assemblies, etc. But I will do some of the smaller, recommended upgrades. Maybe I'll splurge for a cerakote job one day.
Anyway, I have the non mim extractor. I think I'll tackle the mag spring/follower next. Based on what you mentioned, I think I will go with the s&j hardware polymer follower. I see on the S&J site that the follower comes in both type 2 and 3. Which do I want? But what about the spring? What is the proper upgrade for my express? I don't have a mag extension and don't plan on getting one. So what would be the best spring for the stock shorter magazine length?
Lastly, is there a place I can get both items in order to save on shipping?

[Synchronizor]

If you're just working with a standard 4-round magazine tube, your factory mag spring will work just fine. My 4-round spring provides plenty of power for reliable functioning, and I've even cut a couple coils off one end. With magazine springs, there is a point where a stronger spring stops helping, and starts causing completely new problems by damaging the shells in the magazine. Excessive spring pressure will accelerate wear to the follower & shell rims, and can deform plastic or paper hulls over time, leading to unreliable function.

That said, S&J does offer a spring & follower combo package for a reasonable price, or you can buy them separately and still combine shipping if you want a different follower. If you're in the US, you can save on shipping by going through their US distributor.

Note that the S&J springs come long, and you're supposed to trim them to the length that gives you the power & capacity you want. When you trim it, remove coils from only one end, and place the cut end forward, keeping the finished end at the follower.

The S&J Type 2 followers have solid bodies with stabilizing tails. The Type 3 followers are cup-style followers. If you're not using a magazine extension, both should be equally reliable. For the same-length spring, the Type 3 will give you a little extra space in the magazine, so that's what I would go with.