I would question someone's criticism of a well-known product like Algor. I have used it since the DOS days and always found it to be reliable. The DOS linear version was based on the well-known SAP IV program introduced years ago by Ed Wilson at UCB. I heard rumors that this code sometimes produced erroneous results, but I never found that to be true. It was an easy code in which you could incorrectly define a model mesh due to lack of graphics and the load case multipliers were somewhat difficult to apply. In my opinion, Algor brought over some of those complications, but the graphics helped considerably to spot problem areas. I think the Windows version of Algor is much easier to use and the user has considerably less chance to make an error. FEA is a lot like flying...there is a better chance of pilot error than any other cause.
That said, general purpose FEA software is so powerful and complex that there is always the potential for a bug in a seldom used option or problem type. I would ask for specifics from the naysayers.