What's this?! Ruro is evolving!!!

[Zengar Zombolt]

Protip: Vic Viper isn't the main character, it's pilot is.

[♛ Apher-Forte]

is the pilot a loli and hot?

[Prody]

There is no pilot. Vic Viper is the pilot. It's a talking ship in Gradius V.

[Letty Whiterock]

Protip: Vic Viper isn't the main character, it's pilot is.

You are the pilot. Therefore, YOU ARE THE MAIN CHARACTER.

That's deep, man.

[Rin Kagamine]

If we're going to split hairs, the original Vic Vipers were piloted by James Burton, but since he died somewhere after Gradius III, technology has been pushing the Vic Vipers towards full sentience, but the current status of them is unknown, since some are known to have pilots (who identify themselves as "Vic Viper") but the NPC Vic Vipers may very well be sentient.

[♛ Apher-Forte]

and hence Vic Viper is S2 Strike Witches lead character.
 

[Edible]

If we're going to split hairs, the original Vic Vipers were piloted by James Burton, but since he died somewhere after Gradius III, technology has been pushing the Vic Vipers towards full sentience, but the current status of them is unknown, since some are known to have pilots (who identify themselves as "Vic Viper") but the NPC Vic Vipers may very well be sentient.

Came in here to say this, yeah.  Other than James and Leo Stenbuck, though, no Vic Viper pilots have names.

[Suikama]

[Matsuri]

Irrelevant.

1) Reimu is technically the main character of only two games, HRtP and SoEW, because in every game that followed, she shares the spotlight, changing her from "main character" to "playable character." One may argue that the inclusion of Lord British in the Salamander series allows them to be excluded, but Lord British, as Player 2, is very clearly a supporting role.

2) Games outside the official Gradius series still count, such as Life Force (which technically ended up completely different from Salamander), Nemesis II, and the mobile-only Gradius NEO series, because Vic Viper was still the main character of those games. The only related titles that include a playable Vic Viper but don't count are Cosmic Wars (MP Vic Vipers) and Solar Assault (playable character Vic Viper).

3) Excluding doujin games for obvious reasons, Vic Viper is still a playable character is far more games than Reimu (Konami Krazy Racers, pop'n music, Zone of the Enders: The Second Runner, etc.). In addition, though unrelated, the Vic Viper has a few official cameos, such as its appearance in the Sky Girls anime series and as DDR Extreme background videos.

And a few more reasons why the Vic Viper is cooler than Reimu:

1) The Vic Viper is forced to work for its power-ups. Only certain enemies and enemy chains will drop power-up items, items that have to be spent conservatively to be effective. Reimu does start with maximum speed, which is a point against Vic Viper, as it must use constant Speed Ups to reach an effective velocity, but Reimu also starts with two or three bombs (I forget how many) by default. Prior to Gradius III's inclusion of the Mega Crush ability (which still requires a large number of power-up items to use), the only bomb-type item was a blue power-up drop which seldom showed up. This makes "bombing" for the Vic Viper incredibly rare. In addition, Vic Viper must also use said power-ups to change shot types, though said types can be changed on the fly, which is a definite plus during gameplay. However, in spite of all of these disadvantages, Vic Viper has saved the entire universe, not just one backwater, alternate Japanese dimension, more than once, making Vic Viper far more badass.

2) Reimu definitely has potential sex appeal, being a girl and all, so Vic Viper is left out of this one. Or is it? Well, turns out Vic Viper has its own mecha musume version in the form of a 2nd year student at St. Gradius High School named Aoba Anoa, and she's playable in the arcade shooter Otomedius and its 360 port Otomedius Gorgeous.

3) Reimu has a pretty cool soundtrack accompanying her on her journeys, but the Vic Viper's radio cranks out tunes that are unmatched. Specifically, Gradius V's soundtrack was produced by Hitoshi Sakimoto, whose other works include the scores for Final Fantasy Tactics, Radiant Silvergun, and Odin Sphere, and tracks for Mushihime-sama, all of which featured stellar music.

Conclusion, Vic Viper owns. Reimu sucks.

Cue.
Ee.
Dee.

What tracks? This is important.

Also yeah, that shit's deep there. If my copy of Mushihimesama Futari wasn't coming in the mail today I'd be playing some Gradius.

'Smatter of fact, the mail doesn't come for a couple of hours.

*plays*