Well I wouldn't recomend a 10mm for a newb or even an intermediate shooter, but if you've got the other calibers and want something different that everybody and their brother doesn't have it's a nice option.
To really get it's full potential though you need to be into reloading and once again I wouldn't recomend it as your first caliber to start learning on. Most factory loadings are watered down to .40 S&W levels. The .40 was actually based on the watered down 10mm loadings the FBI was using. The guys at S&W came up with the idea of shortening the brass since the load was not using as much powder, and now it would fit in a 9mm sized pistol rather than the bigger .45 size guns a 10mm required. The .40 then quickly surpassed it's parent and the rest is history.
10mm is an amazingly versatile caliber that can be loaded down to .40 levels or up to some really smokin' nuclear loads that reach the .357 magnum and even low .41 magnum levels. Something no other common pistol calibers are capable of. Bullet weights can go from 9mm type 135 gr all the way to 220gr .45 type of weights. The 10mm can be loaded for just about any purpose you want from a pistol.
And don't let people kid you that its some uncontrollable monster that'll rip your arm off. I've owned two 10mm both full-size.
My current 10mm a Glock 20
and a Witness I sold to a friend.
Both offer excellent control and shootability even with the hottest nuclear loads.
Now the Witness loved to fling the brass into the next county but the G20 is no worse than any other pistol about throwing brass. There was a fix on the Witness where some owners were shorting the ejector but I never modified mine.
If you are aware of the 10mm's limitations especially as to ammo availability and that you can't just bop on down to Wally-World to buy a box of ammo but want the ultimate pistol caliber then you won't be disappointed.
