Since you have a high ball flight the Pro V1 might be better, but try a sleeve of each at judge for yourself. If you can get out and play a few holes or maybe even 9 with two balls you could compare them head to head. You could also use the Ball Selector tool to see what it recommends based on your answers.

www.titleist.com/golf-ball-fitting-tool

Probably the ProV1 over the ProV1x if you are looking to lower your flight a bit. Each has different benefits and characteristics. Even the tour pros choose different ones based on the things they are trying to maximize in their games. The best advice I can give is to take both out on the course and play a few rounds with each one and then make your decision. Once made, try to stick with the same model for a while as it is tough to bounce back and forth all the time without it impacting your game. Both are great choices. Good luck.

Use the ball fitter here... Or, get a sleeve of each and work from the green to the tee!

I'll add my 2 cents to Barry's thoughts about playing 2 balls. If you can play two balls on a hole; a par 5 may be best. That way you can hit a driver, a hybrid or mid iron and a wedge, and actually see the difference in each, and will give you immediate feedback on each ball.

low ball flight may mean you don't spin the ball much, which would make the X the better ball. Get a sleeve of both and see which one performs the best for you.

Both work great, use the one that fits your eye and gut

I like the X better because of the lower spin rates

the X has higher spin rates than the regular ProV1