IMO, that is a very good price. The Sentry safes are pretty good for the price interms of having some type of security. They are considerably better than those school locker-type cabinets. If that is all you can afford right now, I think it's a very good deal. Keep in mind though, '14' means if the rifles have had their bolts and scopes removed, and are sandwiched in like sardines. (I have one of those 22 gun ones.) Also, as you probably know, they are relatively light at 250-300#. Okay for moving around but if you can move it around easily, so can a thief. (i.e., bolt it down if you can.) Which particular Sentry 14 is this (product number)?
IIRC, Stack On has started making lower end safes also (beyond their flimsy gun cabinets they are known for) similar to the Sentry safes. Don't know the quality of those though.
As compared to my Browning safes, the Sentry is a bit lower in durability against attacks, IMO, but I think it'll do OK. I plan on directly bolting it to the other safes (from the inside, of course).