Coil tap vs. Coil split pickups - which sounds better?
You probably don't even know the difference between the two. You will after reading this.
Above is a 2015 Gibson Les Paul Studio in Desert Burst (definitely the best color for the 2015 model year.) This guitar does have, in Gibson's own words, coil tapped pickups.
What's the difference between tapping and splitting?
Coil split: A coil isolation technique. In a dual-coil pickup, one coil is literally turned off when split.
Coil tap: A coil winding technique. During the wire winding process of pickup construction, another wire is routed in, usually at the midpoint (e.g. if there were 1,250 winds on a pickup, this wire would be introduced at around the 625-wind mark,) then the rest of the original wire winding process is completed. That midpoint wire introduced is the tapped part, and when engaged will have the pickup produce a distinctively different lower-output sound compared to the regular wire at the end of the pickup windings.
Which sounds better?
Surprise answer! Neither, because they're totally different from each other.
What is a coil tapped humbucker supposed to sound like?
Many players think "coil tap" means "single-coil sound." That is not universally true. You can set yourself up for some big disappointment if you think all coil tapped humbuckers are supposed to sound like single-coil pickups when tapped.
The fact is that some coil tapped humbuckers sound single-coil-like when tapped, while others don't and instead just sound like vintage low-output humbuckers; it depends on how the pickup manufacturer voiced them during construction.
For example, certain coil tapped humbuckers only do one thing. Lower the output when tapped. That's it. It's almost like switching on or off a boost, with tapped being "boost off."
Then there are other coil tapped humbuckers where it's tapped in such a way to have a very single-coil-like character to it (usually depending where the midpoint wire was introduced during pickup construction.) But rest assured, that humbucker is absolutely not acting like a single-coil pickup when the tap is engaged.
What is a split coil humbucker supposed to sound like?
Like a single-coil pickup, because you are in fact physically turning off one coil when you split.
If you want a humbucker that physically switches to a single-coil pickup via a push/pull knob or other switch, you absolutely want split and not tap.
But in the end...
If you want single-coil tone, which is probably what you were after in the first place, use a guitar with single-coil pickups in it and just skip the split altogether.
Will the P90 Paul have single-coil hum? Of course it will. But it will also have that awesome "growly" P90 tone you're chasing after. And the pickups will also be mated to potentiometers with proper resistance for P90s (which should be a linear taper 300K for the volume pot.)
By the way, I'm not saying not to buy the Gibson Les Paul Studio. If you want one, get one. Just don't expect those tapped humbuckers to sound like real P90s or emulate real Telecaster tone, because that's just not happening.
Also, just as a final side note, Gibson does have this thing called "Tuned Coil Tap" with certain pickups they make, which they directly describe in their words as:
...a gentle, but distinctive, midrange scoop - without thinning the sound or dropping the output [and] also [retaining] most of a humbucker’s hum-rejecting properties.
That is Gibson's words on what that type of tap does to the tone in their guitars with pickups that have Tuned Coil Tap. It's not-exactly-single-coil, not-exactly-humbucker in tone representation. It is, more or less, a "filtered" tone (via capacitor) when the tap is engaged. Is it any good? Heck if I know, because I wouldn't bother and just use guitars with real single-coil pickups in them anyway, which, in fact, I do.
Now you know that split and tap are absolutely not the same. Just remember the following: For single-coil-like sound out of a humbucker that you can toggle on/off, split. For a lower-output voicing option out of a humbucker that you can toggle on/off, tap.