General Information

Route Information
Mega Man 3 has 4 routes that have been used over the years. Each has its advantages and disadvantages as far as difficulties go, but most finish within a reasonable amount of time of each other. 
 Top First 
 The old (pre 2012?) and now current (2017?-present) WR route is 
 
 Top 
 Shadow 
 Gemini 
 Needle 
 Magnet 
 Hard 
 Snake 
 Spark 
 
 The key features of this route: 
 
 Top takes 2 damage from buster 
 Gemini takes 2 damage from Shadow 
 Needle gives Rush Jet for Magnet Man's stage 
 
 The primary downside of this route is it is EXTREMELY mash heavy. You will need to use buster on Top Man's cats and the middle section of Needle Man's stage. 
 Magnet First 
 Briefly a WR route in 2015-2017, the Nintendo Power Magnet First route is a beginner friendly and extremely race viable route. 
 
 Magnet 
 Hard 
 Top 
 Shadow 
 Gemini 
 Needle 
 Snake 
 Spark 
 
 Similar to Top First, Magnet takes 2 damage from Buster, and you will have Shadow as a soft weakness for Gemini. 
 The bad difference is you will need to navigate the Yoku Blocks of Magnet Man's stage without utility items, and you will not have Shadow Blades for the Hard Man first screen bees. On the bright side, you will have Magnet Missiles for Top Man's cats and Needle's stage. 
 Gemini First 
 The early 20-teens WR route was Gemini first. 
 
 Gemini 
 Needle 
 Spark 
 Magnet 
 Hard 
 Top 
 Shadow 
 Snake 
 
 This route has an eye on getting Rush Jet early; Gemini is a much more possible Buster fight than it appears with some practice. 
 Downsides include Gemini not having a buster weakness, and Spark not being as fast to kill with a soft weakness as Gemini Man (since there are two Gemini Men to do damage to). You also lose access to Rush Marine as a backup in Gemini. 
 The bright side is you have Rush Jet for a few more stages. You can skip the Yoku blocks in Magnet, and potentially use Rush in Shadow if desired. You'll also have access to the 2 E-Tanks from Gemini Man's stage immediately. 
 Needle First 
 An adventurous few go to Needle First for immediate Rush Jet. This route is less recommended than the other three, but can be fun. 
 Doc Robot Notes 
 Since you have all weapons for all of the Doc Robot stages, the route does not matter. You may want to look for stages with either more resets to do first (to get to the reset faster), or for more E-Tanks (if you're just looking to survive).