Which NFL QBs are worth a No. 1 pick?

Drew Brees, Aaron Rodgers and Andrew Luck are all elite NFL QBs. Are they worth a No. 1 pick? Getty Images

Most of the NFL coaches and general managers I've spoken with think the Houston Texans will not select a quarterback first overall in the 2014 draft. Some of them have sounded familiar alarm bells about over-drafting quarterbacks, and for good reason.

NFL teams have selected a dozen QBs first overall in the past 16 drafts. Peyton Manning is the only one with Hall of Fame credentials, eight of the other 11 could qualify as disappointments and a couple of others are just getting started. So, by all means, sound those alarm bells, but remember also that the non-QBs selected first overall during the same 16 drafts were less than sure bets. Jake Long, Mario Williams and Courtney Brown enjoyed varying degrees of success, but none signed a second contract with his original team. The fourth non-QB on the list, Eric Fisher, is still getting his career started.

While the Texans consider their options, I thought it would be interesting to consider which current NFL quarterbacks would be worth a No. 1 overall draft pick based strictly on current playing ability, without regard for age or salary.

Peyton Manning, Aaron Rodgers, Tom Brady and Drew Brees would obviously qualify, but where would seasoned personnel evaluators draw lines of demarcation? Would they put Robert Griffin III, Russell Wilson or Colin Kaepernick in that group? What about Matt Ryan, Eli Manning, Matthew Stafford, Tony Romo and Ben Roethlisberger?

The sometimes surprising answers I got from ESPN analyst Bill Polian, ESPN.com NFL scout Matt Williamson and an NFL general manager provide pre-draft fodder and, perhaps, some context for the Texans' decision as well. There were seven unanimous selections and a couple of potential omissions.

Polian: Brady, Peyton Manning, Rodgers, Brees, Andrew Luck, Roethlisberger, Wilson, Philip Rivers, Ryan, Eli Manning, Cam Newton (with an asterisk, for reasons outlined below)

Williamson: Brady, Peyton Manning, Rodgers, Brees, Luck, Roethlisberger, Wilson, Rivers, Ryan, Newton, Romo, Stafford, Joe Flacco, Griffin, Ryan Tannehill, Jay Cutler, Kaepernick

NFL GM: Brady, Peyton Manning, Rodgers, Brees, Luck, Roethlisberger, Wilson, Eli Manning

Using this input as well as my own opinion drawing on discussions I've had with evaluators previously around the league, here's how I'd stack up the quarterbacks worthy of trading a No. 1 overall pick for. I've arranged them in tiers: "Clearly worth a No. 1 overall pick," "Close but not quite," "You could make an argument for them" and "On their way, but not there yet."

Clearly worth a No. 1 overall pick

1. Peyton Manning, Denver Broncos

Of the seven unanimous choices, only Manning and Luck were actual No. 1 overall selections.