The fully-evolved starter Pokemon are scattered throughout the BW tiers as of today for various reasons. Some have good stats but poor movepools, some are vice-versa, some are outclassed by other Pokemon, etc. Here is, for reference, where each one is as of now:
Uber
Blaziken
OU
Venusaur
Infernape
UU
Blastoise
Swampert
Empoleon
RU
Typhlosion
Feraligatr
Sceptile
Emboar
NU
Charizard
Meganium
Torterra
Serperior
Samurott
This thread is meant to discuss what the (fully-evolved) starter Pokemon in NU do, how effectively they do it, and which ones perform the best at specific roles (sweeping, walling, providing hazards, wallbreaking, etc.). Here are the candidates:
Common roles:
Sun abuser
Revenge killer
Pros:
Excellent offensive coverage
Excellent stats for sweeping
Solar Power
Setbacks:
Frality
Double Stealth Rock weakness
Common roles:
Cleric
Phazer
Status inflicter
Pros:
Great bulk
Dual Screens
Many status options
Setbacks:
Lot of competition from other Grass-types
Very little offensive presence
Common roles:
Hazard setter
Tank
Cleaner
Pros:
One of only two fully-evolved Grass types in NU to get Stealth Rock (the other is Cradily)
EdgeQuake
Well-balanced stats besides speed
Setbacks:
Very slow
4x Ice weakness
Common roles:
SubSeeder
Support/Cleric
Substitute + Calm Mind sweeping set
Coil sweeping set
Pros:
Top-tier speed for NU
Wide variety of support options
Taunt + Substitute
Good defenses
Setbacks:
Terrible offensive coverage (no Rock Slide?!)
Poor offensive stats for sweeping
DW ability unreleased (but Serperior will probably be out of NU when it is released)
Common roles:
Wallbreaker
Sweeper
Pros:
Excellent attack and special attack
Good coverage options
Decent defenses for an offensive Pokemon
Can go mixed very well
Swords Dance
Cons:
Super-effective moves are extremely dangerous
Lacking speed
Besides discussing how these Pokemon do their standard jobs, this is also a chance for you to post new/creative/unheard of sets for any of these five Pokemon, and hopefully eventually the community will come to a consensus on which one is overall the most effective in NU.
P.S. Don't immediately start posting stuff like "Samurott is the best since it's so high on the ladder." Remember, we are comparing these five Pokemon to each other.
Uber
Blaziken
OU
Venusaur
Infernape
UU
Blastoise
Swampert
Empoleon
RU
Typhlosion
Feraligatr
Sceptile
Emboar
NU
Charizard
Meganium
Torterra
Serperior
Samurott
This thread is meant to discuss what the (fully-evolved) starter Pokemon in NU do, how effectively they do it, and which ones perform the best at specific roles (sweeping, walling, providing hazards, wallbreaking, etc.). Here are the candidates:

Common roles:
Sun abuser
Revenge killer
Pros:
Excellent offensive coverage
Excellent stats for sweeping
Solar Power
Setbacks:
Frality
Double Stealth Rock weakness

Common roles:
Cleric
Phazer
Status inflicter
Pros:
Great bulk
Dual Screens
Many status options
Setbacks:
Lot of competition from other Grass-types
Very little offensive presence

Common roles:
Hazard setter
Tank
Cleaner
Pros:
One of only two fully-evolved Grass types in NU to get Stealth Rock (the other is Cradily)
EdgeQuake
Well-balanced stats besides speed
Setbacks:
Very slow
4x Ice weakness

Common roles:
SubSeeder
Support/Cleric
Substitute + Calm Mind sweeping set
Coil sweeping set
Pros:
Top-tier speed for NU
Wide variety of support options
Taunt + Substitute
Good defenses
Setbacks:
Terrible offensive coverage (no Rock Slide?!)
Poor offensive stats for sweeping
DW ability unreleased (but Serperior will probably be out of NU when it is released)

Common roles:
Wallbreaker
Sweeper
Pros:
Excellent attack and special attack
Good coverage options
Decent defenses for an offensive Pokemon
Can go mixed very well
Swords Dance
Cons:
Super-effective moves are extremely dangerous
Lacking speed
Besides discussing how these Pokemon do their standard jobs, this is also a chance for you to post new/creative/unheard of sets for any of these five Pokemon, and hopefully eventually the community will come to a consensus on which one is overall the most effective in NU.
P.S. Don't immediately start posting stuff like "Samurott is the best since it's so high on the ladder." Remember, we are comparing these five Pokemon to each other.