I'd like to acquire a p'up for my Fender acoustics; but the plethora and variety of offerings are mind-boggling! These two guitars are great sounding, easily playable but inexpensive. I don;t want to spend huge $$ and exceed the cost/value of either. Just a basic, decent, entry level pick-up.
I believe local GC would flip if I started at one end and ran thru the case to the other using the "30 day return" guarantee Side-by-side comparison would be impossible with that scheme, anyway.

I'd like the one p'up to do double-duty for the 6 string AND the 12; at least to start with. Perhaps a sound-hole mount would be the way to go for swapping out the p'up? Prefer a bright sound. Mostly folk/pop style. Some finger-pick, lotsa flat pick, mostly strumming accompaniment

The Markley Pro-mag series looks interesting and within price range...$49-$69. Lotsa options in this series to ponder. DiMarzio has a similar sound-hole unit in the DP-135.

I'm supposing I will NOT need a pre-amp, as I'll be running the unit thru an Acoustic B-50 amp?? ..or would it be needed/not needed running thru the Fender 65R?

Early stages of discovery yet. Any input will help shorten the quest.

If you want to use the PU on a couple of different guitars, then a sound-hole job is the way to go. No, you don't need a pre-amp; they just plug into the amp and off you go. Some models even have a volume control built-in.
As to recommendation, I can't give you one. Most soundhole pickups are electromagnetic and sound rather like an electric guitar.....Specifically a hollowbody electric. If you like that sound you're golden. Some models incorporate a piezo (vibration sensing) element as well, and these may produce a more "acoustic" sound, but also tend to cost more.
Just mike up the guitars, natural sound and only the cost of a mike. Its really good for rhythm
guitaring because you can accentuate your playing with a little movement.

i have never liked accoustic through fender reverb it just doesn't work, and i dont have any experience with B50. I use Behringer ultracoustic or AER. However i do put my Takimine 12 string through the Marshall amp and its magic. Cheers
Picked up a Dean Markley Pro-Mag Grand last week at GC. This is the hi-end one...was $119. on sale for (the same as the inexpensive one) $49.00 !! Sounds quite good thru the Acoustic amp; very brite and responsive. Thru the Fender, it ...well...sounds more like an electric, as bikewer sez.?!?! but that's what I'd expect from a humbucker-equipped hollow body...right?

What I find missing is the resonance, the full, warm vibe of an acoustic. You know... that volume and tone that fills the ...ahem..."gaps" in technique. Surely can't get away with raunching a chord or dropping a finger wrong when each string is amp'd I suppose it will force me to work on those deficiencies a bit more. LOL

Next trial will be a "drop in" mic type of PU. I've tried a few set-ups mic'ing up and none seemed satisfactory AFA placement and movement.

*anecdotal edit*
Years gone by, I duct-taped taped a transistor radio earplug, sans inner ear extension, to an old arch-top acoustic. While it couldn't keep up with the true electrics, it *did* pick up well; if 40-some y.o. memory serves. A quick rummage thru the old parts bin might be enlightening.

Thanks all,
K&K Pure Western Mini are the best pickups out there today
Esp Eclipse II
Fender Strat LoneStar
Martin D35 Custom Shop
Vox Night Train
Vox Heritage cab 1x12