As Skribs said, if this is the only way that you can carry, then it is the best way for you.
Some of the "cons" can otherwise be:
1) Cross-draw is measurably slower than a strong-side holster. I know a lot of people will say, "not for me!!!" but without the numbers recorded off a shot timer, that's not credible. You must reach farther and must turn the gun and present it in a motion that sweeps around to get on target, meaning you cannot use the "4-count" draw stroke and cannot fire until your draw is complete.
2) Further, the end of your draw is in stopping a horizontal sweep to land on your target, instead of punching the gun straight out at your target, making your first shot accuracy tend to suffer. (Think that isn't so? Set up the targets and the timer and prove it to yourself!)
3) The cross-draw draw stroke is easily blocked/fouled. If you are in a situation where you're truly fighting for/with the gun, an attacker who grapples with you can with some ease bind your strong-side arm, or get his body in the way so you can't snake your hand across to the opposite side to grasp your gun. There are some techniques to minimize that problem, but you'll have to practice keeping your body clear enough to get your firing hand over there. Conversely, the strong-side draw-stroke is very hard to foul or block.
3a) While someone who grapples with you can block you from grasping your gun, your gun is oriented in a way that makes it most easily grabbed by someone facing you.
4) Most ranges, and all competitions, prohibit the use of holsters that orient the muzzle up-range when holstering or drawing (so no cross-draw, shoulder rigs, or SOBs). That can make it difficult to get the critical practice time in with your carry equipment.