There certainly are. Can I just say to begin with that I am not trying to disrespect the Reds when I say I have doubts about their pack's ability to win finals against the very best teams. I live in QLD and they are by far and away my favorite Australian team.
Firstly, their pack is relatively inexperienced. Both in terms of Super Rugby and test caps. Experience comes to the fore during finals, and the Reds pack is certainly less experienced than any of their top four rivals. During finals, the pressure and intensity of play lifts markedly when compared to regular season games. Experienced players are often in a better position to deal with this pressure. The Reds pack lacks experience to draw upon.
Secondly, the none of the Reds forwards have won a Super Rugby finals match. They have not shown that they can take their game to the next level, and deliver under finals intensity. Contrast this to the Stormers, Crusaders, Bulls and even Sharks packs, who have all won semi finals over the past 3-4 years. Given that none of the current Reds players have ever won a finals game individually, let alone as a team, I think it's clear why people like myself might doubt their ability to win finals until they have shown that they actually can.
Thirdly, how many genuinely world class players does the Reds pack boast? Whilst Rugby is clearly a team game, and a champion team will always beat a team of champions, personnel does make a difference. The quality of players in a team does make a difference. Even at Wallaby level, there will be few Reds forwards in Deans' first choice 22. Whilst there a few young Reds forwards whose stars are certainly on the rise, I think it's understandable that people like myself might doubt their ability to compete with the very best packs in SANZAR which are over-flowing with All Black and Springbok stars.
Lastly, my sceptism towards the Reds pack, and team more generally, is based largely on what happened in 2010. They looked like absolute world beaters last year, until a late season fade saw them miss out on the semi finals. They still have to show that they can maintain their form late into the season, and peak when it counts come finals times. Plenty of teams have looked good mid-season, only to crumble under the pressure and expectation of an impending finals series, and until the Reds show otherwise I will have lingering doubts about their ability to win finals.