If you want to use Soft Lock on some of the harder missions in NYM then I say go for it. I did it myself and I have both NYM and NYM Hardcore completed. Took me 8 tries for NYM Hardcore just to give you an idea.
100% Completed: 191
Total Games Played: 197
Current Percentage: 99% (Screw you Ninja Gaiden II & Trials Evolution)
Currently Working On:
Grand Theft Auto V, Rayman 3: HD & Call of Duty: Black Ops II
On The Back Burner: