I have both My excal has a straight shaft, a remote pinpoint, ctx connectors for headphones and quick disconnects for the coils. I have a 17, a 15 and a 10" coil for the excal.
The CTX, I have all three. The 17" the 10" and the 6". 6" is for parks and when erosion gets VERY low.
Preference? I can tell you that on EVERY hunt I bring BOTH detectors. I've had times where I took the excal and the beach had me falsing like a mo-fo. completely useless regardless of sensitivity settings. I'd then run and get my CTX and it'd be smooth as silk. Other times, just the opposite.
I prefer to hunt in the deeper water hunts with the excal. No guess work. If a tone hits in discrim and pp, I'm digging it! .. The CTX can be a guess game but it does kill it with iron discrim. And as mentioned the CTX is harder to swing in the water. I've pretty much waterproofed the holy heck out of the CTX but it still gives me doubt. 3 yrs of hunting and still no water intrusion except for the external speaker which recently got replaced on warranty. The CTX's 17" coil is nice on the dry but can be hard to correctly tell where to dig sometimes as it halo's quite a bit. Nothing beats the excal in deeper water with the stock coil..
In the water the CTX's headphones SUCK!!!! I've tried em all.
I recently made some waterproof ear buds w/ctx connectors. Took them out today for the 1st time actually in shoulder deep water. I used some ear muffs over the buds and WOW... VERY LOUD... I was actually impressed. Got 2 silver rings, 3 silver quarters. No gold today sad to say...
The main reason I got the CTX was to ID pennies and decide if I wanted to dig them or not... They annoy the poop out of me. Most of the time I dig them regardless but when you're salted with pennies from a ... penny seeder especially ones with holes in them, it's nice to walk on by w/o a worry.
Finally, a machine is only as good as the person behind it. Read your beach, know conditions, understand where targets rest (yes there are fresh drops but what fun is that?) is what it's all about. I see so many people shuffling though different types of machines w/o learning them. It's almost tragic.