Re: Smith&Wesson night Gaurd 10mm!!
The S&W 310 Night Guards are nice revolvers (typical of S&W revolver quality) but like every revolver chambered for a rimless cartridge...you are screwed/stuck with moon clips which can be annoying and a general inconvenience at times (although I admit I own a .45ACP competition revolver).
A 10mm revolver is just sort of a bastard compromise IMO for a revolver based on the NUMEROUS other options for chamberings that are vastly superior to the 10mm and make better sense for a revolver. It is great as a semi-auto pistol cartridge given the amount of power it offers in a relatively small package, but it pales in comparison (given its lighter bullets and lighter loads) than numerous common revolver chamberings. I guess it all depends on what your plans are for the gun as to whether it is a good option for you or not. Regardless of all that, you got the pistol for a steal at only $550 (which is $200 cheaper than I have ever seen one for sale) and it should be a lot of fun to shoot. If you don't like it or you want something else...I'm betting you won't have any difficulty getting your money back out of it (and maybe more).