I really can't tell the difference between a $400 EOTech and a $50 generic red dot. I cannot figure out what makes them so expensive, other than assumably being more durable...but you're not going into combat.
Why is there no middle ground between cheapo stuff and 'costs as much as some people's entire rifle' stuff?
For plinking anything that holds zero works.
I've owned and used the following electronic sights (except the ELCAN and ACOG, I demo'd those for a day):
ELCAN Specter 1x-4x
Trijicon ACOG (various flavors, yeah I know this isn't electronic but it's illuminated)
Aimpoint PRO
EOTech XPS 2-0
Sightron 30mm Multi-Reticle
Bushnell TRS-25
Primary Arms Micro Dot
Primary Arms 30mm Red Dot
ELCAN Specter ($$$$) is very nice with a throw lever to switch zoom. Made for combat use and with the mag capability is good close up as well as max range of an AR15. I was impressed with it, but I've heard many others say it doesn't stand up to hard combat use as well as an Aimpoint or ACOG. Since I don't have personal long term experience with it it's hard to say. Made in Canada.
Trijicon ACOG ($$$-$$$$). Beautiful optics across their line, but pricey. That's because they're built for combat and can take a lot of abuse (I've seen some that looked like they should be broken, but they still worked fine... and looked fine after some rattle can ). As with all high ticket items make sure you get to look through a couple before you make the decision to buy. Great for longer range AR use with the ballistic reticles. Made in USA.
Aimpoint PRO ($$$) is a very nice, waterproof/shockproof red dot. Again, built like a tank for combat use and the quick release thumbscrew is good and mostly maintains zero when removed. Extremely long battery life. Like 2 years left ON and never turned off. Made in Sweden.
EOTech XPS ($$$) is the best (IMO) EOTech due to transverse mounting of the battery. I've heard from too many hard users of ARs that their EOTech 512s would blink on and off with recoil after a while due to the recoil wearing out the battery compartment spring. With it mounted sideways in the XPS series that's not a problem. EOTech is the best for accuracy as it has a "1 moa" (actually, < 0.65 moa) center dot. Especially if you have a flip to side magnifier behind it (but then that setup is as heavy as a scope...). Battery life significantly worse than Aimpoint (500-600 hours?). Made in USA.
Sightron S33 multi-reticle ($$$). Comes with rings which are a bit fragile but have worked for me. I use this on my shotgun (Rem 887 Tactical) and it has handled the abuse of 12 gauge for hundreds of rounds without any shift in zero. Battery life is nowhere near the Aimpoint, but since it uses cheap batteries not a big deal. Multiple reticles with no zero shift changing between the four reticles. Even has one with a 1 moa center dot - I choose to use a dot within a circle for rapid target acquisition and have gone trap shooting with it. Very bright even on low brightness - the brightest red dot I've seen. Made in Japan.
Bushnell TRS-25 ($$). Decent 3 moa red dot. Can take a little bit of abuse, is lightweight, and gets the job done. This or the Primary Arms are decent solutions for plinking at the range within 100m. At this price point you may get the occasional lemon and don't expect the dot to be perfectly round - they need to cut corners to make it cheap, after all. Also, battery life around 1000 hours, much less than an Aimpoint. Made in China.
Primary Arms ($$) - pick your favorite design. They're all about the same in terms of quality, and roughly comparable to the Bushnell TRS-25. Battery life < 1000 hours. Made in China. But Marsh from Primary Arms will take care of you if you have any issues with your red dot.
Let me know if you have any specific questions about any of the above. My opinion is that for the average infrequent shooter it won't make much of a difference what you buy as long as it maintains zero. Those who care about long range accuracy will generally use scopes anyways, so red dots are pretty much out of the picture for > 300m shooting. Those who care about close range work or duty use will generally prefer the Aimpoint due to zero mag + reliability (never turn it off, 2 years+ battery life). Or the EOTech due to quick target acquisition and its superior reticle.