The difference between a 2-color and 3-color sunburst guitar finish
Sunburst is a guitar color finish option that's been available for a very long time; it's always been popular because it has a woody/furniture look to it.
It's called a sunburst because the middle of the body is supposed to be gold (as in "sun like") in color where the burst starts, then towards the ends of the body the color fades to a much darker color or all the way to black, which is where the burst ends.
There are many different kinds of bursts out there, but the two most popular are 2-color sunburst, commonly called "Two Tone Sunburst" or 2TSB for short, and 3-color sunburst, commonly called "Three Tone Sunburst" or 3TSB for short.
An example of a 2TSB is the "Brown Sunburst" option on the Mexico-made Fender Standard Stratocaster:
An example of a 3TSB is the "3-Color Sunburst" option on the Fender American Standard Stratocaster:
You can see there's a difference between the two.
What's the third color of a 3TSB? Red.
A 2TSB is either natural/brown/black or just brown/black.
A 3TSB is either natural/red/brown/black or red/brown/black.
Which has the more vintage look to it?
This is where things get interesting.
2TSB is always the more vintage-looking of the two, mainly for the reason the beginning of the burst is brighter. The start of the burst is more gold in color and from that you can see more wood grain.
This is evidenced by the fact the Fender American Vintage '56 Stratocaster in sunburst is in fact a 2TSB:
Is the '56 burst exactly the same as the Mexico-made Standard? No. There are three main differences between a Mexico-made 2TSB and the American Vintage Series. Subtle, but noticeable.
The first thing is that the Vintage starts going to black sooner than the Standard, and that the fade is longer. You can see this on the top horn most as there is more of a pronounced "point" compared to the Standard.
The second thing is that more careful attention is given to body wood selection with the Vintage over the Standard. True, both the Vintage and Standard use alder bodies. But the wood grain on the Vintage will be straighter. And yes this does make the Vintage look better because your eye isn't drawn away from the burst by "odd" wood grain lines.
The third thing is the coating. The Standard has a polyester coat, while the Vintage has lacquer. Lacquer can be made to gloss so much that it almost looks like liquid. You can do that with polyester also, but it will lose that liquid-like shine quickly. What Fender does with the Vintage is "flash" coat the lacquer on; I assume they purposely apply a thin coat so it breaks down quicker as certain players want it to chip, crack and peel for that "well played" look early on in the guitar's life.
Does this mean the '56 has a better finish? No. It just means it's different compared to the Standard. The Vintage '56 will shine more at first, but also will chip, crack and peel first as well. The worst that will happen to the Standard is that it just won't shine as much over time.
3TSB is something many players consider "too modern" (on Fender style guitars)
3TSB is not the classic sunburst look that so many players are familiar with, and will always be seen as a modern color option. This is not to say 3TSB is bad, because it isn't. It looks really nice, actually. And when you want a burst with a modern look, it totally works.
Fender's American Standard Stratocaster has very few vintage-style color options. In fact, out of every color option available right now, only two exist that could be considered vintage-style, that being Olympic White and Black. Every other color is modern.
Color was incidentally one of the main reasons why I bought a new Squier Bullet Strat in Arctic White back in 2010. That color has a banana yellow-ish look to it that just looks cool.
But anyway, if I had to choose between the sunbursts of American Standard and the Standard Stratocaster, I'd go with the Standard. I just think it looks better because there's much more gold in the middle.
On a final note:
What's the best low-budget guitar that has the best burst for its price point?
Dean ZX in Trans Brazilaburst, no question.
This is technically a 3TSB as you can see the red in there. And you'll be amazed at how inexpensive the guitar is.
You can't beat the Dean ZX when it comes to getting a look-at-me guitar for the cheapest possible price. Because of the larger Explorer-style shape, it takes to a burst even with the red in it very nicely. That, and it looks way more expensive than it actually is.
How does it play or sound? I have no idea, but I can take some good guesses.
The ZX is a 24.75-inch scale, meaning it probably plays like a Gibson. It has a Tune-O-Matic bridge, and that's easy to set up. No vibrato, so no need to worry about that. The tuning machines are listed as Grover, so they don't need to be upgraded.
If the guitar sounded terrible, that's fine because the electronics are simple so it's easy to pop in a set of replacement humbuckers. I'd personally put a cheap chrome-cover set in it, keep the white pickup rings, and that would complement the bridge and V-shape tailpiece very nicely.
In other words, you can get yourself a seriously good looking burst axe with the ZX for dirt cheap. It's the easiest and cheapest way to get a show-off guitar.