I think that would be a colossal error. Both plans. Murray, McCarron or Mettenberger? Yuck. Sorry man but that sounds like a nightmare to me.
Waiting until the second seems like the best way to miss out on your guy. If there's nobody we like in the first, fine, wait. But it's the QB position. Most important position on the field, you don't skimp on that position.
The objective is to bring Sam back so you don't have to rush the rookie in and can be competitive right away. The objective isn't that Sam is the QB of the future. I mean, I hope he is, but I can't wait around for it anymore. If you're spending a 2nd or 3rd on a QB of the future, you better be damn sure the guy you're getting is going to be good and you better have a damn good reason why he fell that far.
Because, since 2000, the only QBs who have turned into long term starters from the 2nd round are Brees, Dalton, and Kaepernick. Dalton and Kaepernick are both average to above average QBs at best. Geno Smith, Garoppolo and Derek Carr are yet to be seen. That's out of 18 QBs. Even if all three of those guys pan out as long term starters, that's still only 6 of 18(33%). And if we remove those 3 entirely, that's 3 of 15(20%).
If you look at the first round, outside of the top 10 picks(assuming we're less likely to draft a QB if we're out of the top 10), you're talking 5 of 15(33%) if you remove Manuel, Bridgewater, and Manziel. If you assume they make it, that's 8 of 18(44%).
Finally, if you look at QBs picked in the top 10, you have 9 of 18(50%) if you omit Tannehill, Locker, Griffin, and Bortles, and that's counting Bradford as not being a long term starter which would end up being wrong. If you assume all those guys make it, you have 13 of 22(59%).
So, obviously, your best bet is picking a QB in the top 10 and the further you get, the less chances are of finding one. You're talking 50% in the top 10, 33% in the first round without the top 10, and 20% in the 2nd round.
As an aside, as much as I'd hate losing LaMarcus Joyner, I really wish we would have traded up for Teddy Bridgewater. This is with some hindsight because I thought Sam could be our guy and I never expected the injury but I also believe(d) that Bridgewater is going to be a really good NFL QB if given time and developed properly. The guy falling as far as he did was a huge mistake and one we could have capitalized on. But I can't say that I didn't disagree with what they did at the time. Just some hindsight speaking here.