Keys Sticking in Landlordlocks ICores

[Douglas Krofcheck]

I've only heard great things about the Landlordlocks system, except their price, but that hasn't been my experience.  The locks have been very difficult to use.  The keys are annoying to push in and very difficult to remove.  They often get stuck and you have to stand there wiggling it a lot and re-checking alignment.  After spending all that money to rekey the house, the tenants want different locks.  

Has anyone else had this problem with their icores?  I haven't applied lubricate yet, so perhaps that's my problem.  Any recommendations?  Landlordlocks sells Houdini on their website.

Thanks.