I bought a pair of 12" pigtails just a couple of years ago to replace the originals. The replacements are already cracked in places because they make a very tight radius to get to the tank connectors.
Not only would I go with the longer pigtails, I am also looking for the right brass fittings to remove at least 90 degrees of the flex so that the tubing only arcs in one direction from the regulator to the tank.
'12 F250 4x4 Super Duty PowerStroke 6.7 diesel
2011 to present: '11 Cougar 326MKS
1999 to 2011: '99 Sunline T-2453
Amateur Radio kd2iat monitoring 146.52