I don't really understand your question. An acoustic with a pickup installed by a factory and an acoustic with a pickup installed by a luthier are the same thing. The more important question is what pickup to install, and what you want it to sound like. Some pickup systems are more prone to feedback than others. Some reproduce the sound of the guitar accurately, and some are more edgy, more like an electric guitar.
Undersaddle transducers (piezo type)- These are the most common type, and are mounted under the saddle. This requires drilling a small hole under the saddle, and usually requires adjusting the saddle height to compensate. It may require adjusting the saddle slot to fit the transducer.( Don't try to do this yourself.) They are usually active, and require a preamp with a battery mounted to the endpin jack or somewhere else in the body. They are pretty feedback resistant, but can produce volume spikes when the strings are hit hard (piezo "quack"). I prefer them for fingerstyle more than hard strumming. Not so hot for playing The Who. Some have a separate piezo element for each string, intended to improve balance between the strings. These are usually called hexaphonic.
Magnetic pickups- Like the pickups in an electric guitar, they respond magnetically to string vibration. Very feedback resistant, they can sound "warm". They sound good in a cheap guitar, as they don't care that much about how the body resonates. They require no skill or special tools to install. The connector can hang out of the soundhole, or go to an endpin jack. Thay are usually passive, but not always. You can move one from one guitar to another literally in seconds. They do have that slightly edgy semi-electric sound, so if you are a real tonewood purist, it may not be your first choice.
Soundboard transducers- These systems work like a piezo, but instead of under the saddle, they are attached to the underside of the top of the guitar. They respond to the vibration of *the body*, instead of the strings, which produces a "woody" tone. Also- if the guitar sucks, it will suck. On a great guitar, they can sound great. They are very feedback prone, too. Great for a solo coffeehouse with a vintage Martin, right out for a loud band with a cheap guitar. Having sophisticated EQ run by someone with a clue helps, too.
Guitar mics- These can be mounted internally or externally. If internal, they tend to be "boomy", and need a lot of EQ to reduce excessive bass. If external, they can pick up sounds from other instruments or external sources (bleed). They generally require a PA or acoustic amp with phantom power. Both versions are very feedback prone, and work better if you have a good guy on the board, and in smaller venues. I think they generally are best as part of a multiple element system, to add a little "air" to a piezo or magnetic system.
Multiple element systems- These include some combination of the above. This makes them more versatile, but requires more installation, and more stuff inside the guitar. They are more complicated to adjust, and you have to have a blender, (mixer) either mounted in the guitar, or externally, so you can adjust the different elements individually. The most sophisticated systems have separate preamps and EQ for the different elements.
Here are just a few examples of the different types. There are many more, but these are a few that are proven. I've selected generally less expensive models, as they go:
Undersaddle piezo:
L.R. Baggs Element
D-Tar Wave-Length
L.R. Baggs Hexaphonic
Magnetic Soundhole Pickups
Lace California Acoustic (wicked cheap- single coil passive)
Fishman Neo-D (single coil passive)
Fishman Rare Earth Humbucking (double coil active)
Seymour Duncan acoustic tube (double coil passive)
Soundboard Transducers:
L.R. Baggs iBeam (comes in active and passive versions)
Fishman SBT-E
Mic systems:
AKG C516 (internal)
K&K Sound Silver Bullet (internal)
K&K Sound Meridian (external)
DPA 4099G (external and pricey- to die for)
Multiple Element systems:
(undersaddle piezo/mic)
L.R. Baggs Dual Source
Fishman Ellipse Matrix Blend
(magnetic/mic)
Fishman Rare Earth Blend
Seymor Duncan Mag Mic
(magnetic/undersaddle piezo)
Dean Markley Trilogy
(undersaddle piezo/soundboard transducer)
L.R. Baggs iMix
(sound board transducer/mic)
K&K Sound Trinity Mini
The biggest advantage of mounting your own pickup system is- you get the one *you* need/want, instead of a standard undersaddle transducer. The downside? it simply costs money to have it done right.
Personally, I recommend getting the guitar you want, and just dropping in a Seymour Duncan acoustic tube. If you don't like the sound, you're not out that much money, there are no holes in your guitar, and you can move it to another guitar, sell it, or keep it for a backup and use it when feedback is an issue. For my own purposes, I use the Lace California in my cheap beater, and a Fishman Matrix Blend in the Taylor. Hope this helps-Richie
