In a red dot, I find the tube style (think Ultradot) easiest to use. It is easier for me to "find" the red dot, looking through the tube. Ultradot brand has been at the top of the heap in this category for decades for a basic red dot, and the basic models are not overly expensive. I've got a pair of them. One is slightly older, but it still works. I liked it well enough that I purchased my "new" one in 1991...
In the reflex style, I personally have a harder time "finding" the dot. In fairness, I probably haven't shot it enough to make it feel intuitive. For ME, if I can't find my dot in a reflex sight, I virtually always need to point downward a little bit.
Regarding dot size- think about the distance you'll be shooting, and how big a dot you want to "see."
Example 1- If you have a 2 MOA dot, it's only covering 1/2" at 25 yards. Precise for squirrel hunting, but harder to find for rapid-fire plinking.
Example 2- If you have an 8 MOA dot, it's covering 2" of target at 25 yards. You'll cover a squirrel's head at 25 yards, but the dot is easier to find for rapid-fire plinking.
In "traditional" scopes, magnification is available from 1X (no magnification, just nice crosshairs to see) on up to 12X. You need to have your eye better centered behind the scope, or your view "blacks out." If my arms are wobbling, my view in the scope is vacillating between crosshairs and blacked out. This can be distracting/frustrating.
It's hard for me to hold anything beyond 2X still, with my arms extended. Resting against a tree trunk while squirrel hunting, I might get away with 4-6X. With my Contender on a bipod and lying in the prone position, I can utilize high magnification…
I've accumulated a decent collection of optical sights for handguns. Each has its ideal place/time.
I'm at a point in life where I only buy quality stuff. Life's too short (for me, anyway) to buy crap, and constantly have troubles. With a little scouting, you can find bargains on the Classifieds here, eBay, etc.
Within the last month, I bought a Leupold M8 fixed 2X LER (long eye relief) pistol scope for $160
shipped, on one of the forums. Admittedly that was a sweet deal, but they're out there…
A 2X Leupold should last a lifetime, and its lifetime warranty reflects that. An Ultradot sight could very well last a lifetime, and its lifetime warranty reflects that (original purchaser only… keep your receipt!
).
Whatever you choose, look at mounting options carefully. There are tons of options to mount various sights on various guns. Some of the older/cheaper mounts (especially "universal" mounts) are cartoonishly large, high, etc. I like a setup that looks "clean," and sits as close to the bore as reasonably possible.
I'm not always a huge fan of the classic Weaver mounts, but they're cheap, lightweight, and widely available for a huge variety of applications. They also sit nice and low, with a ton of various rings that will work with them…
My Burris FastFire sits on a mount that's inserted into the rear sight dovetail of my Ruger MKII. Not a quick-change setup, but it's absolutely "sano," as the street rod/chopper guys would say...
We have an "embarrassment of riches," as far as options!