Both options are valid. LOL Big help ;-)
I used to use boots to go anywhere, even for a 30 minute ride to an instructors place.
However, when I sold my good fellow - who I should have kept ;-( The truck company flat out refused to travel him with them on. They said they over heat in them etc. causing leg problems. I was highly concerned about my precious boy travelling for the next 30+ hours without them, even over night on a boat, for 12 hours standing in the truck.
They said all shoes had to be off and the horse would be fine. They also insisted on no rugs. But it was on an enclosed truck with multiple horses ;-) I normally like to travel with a light rug, even if it is a cotton one.
So I travelled him on my float to meet the truck for 1 1/2 hours. He has his boots on and a light rug, as I left a 5am. When I unloaded him I took it all off. He arrived perfectly safe to his new owners and sustained no injuries. But not every horse travels well.
Not long after that I travelled to pick up the kids first pony, I did not have any boots small enough for her. She travelled in a float by herself for 8 hours and arrived perfectly fine. And I have to say that since then I have not used boots for every trip. I assess each horse, the mode of transport and I weigh up the possible outcomes. So with two horses on I always use boots, because one can damage the other etc.
IF I ever found a nice horse again I probably would, as I do like to be on the safer side. My float is fully enclosed so I do need to be aware of how hot the horse might get over long distances. When we travel to polocrosse tournaments I like to use boots and we stop once every hour or two to check them temp wise. I take off the rug before I take off the boots.
I was returning a horse to some people a couple of years ago and they said not to use leg boots. So I loaded him on and just as I was about to drive off he threw an absolute hissy fit. He destroyed the inside of my float and even managed to bring down the centre dividers. When we looked over the back he was lying in a heap on the floor amongst the metal.
Hubby somehow managed to gently lift each piece out over the back tail gate, as the horse stayed still. Once the last bits were out he then got back up. I was thinking that I would have to take him off and not travel him. I phoned the owners and they said to still bring him? So I visually checked him and was satisfied that he looked ok and was not showing any signs of distress (or I would have refused to travel him). He then travelled fine for the whole trip.
When we arrived (we met 1/2 way on a 8 hour trip - 4 hours each) I was expecting him to show some sign of lameness, anything. But he was perfectly fine. He just had a few bits of skin off his head and neck. They then loaded him up (they were a bit agricultural ;-) and drove home. They then told me the next day that they rode him that arvo and jumped him!!! I did not maintain contact with them after that.
My point is that some horses will hurt themselves doing nothing and others will chuck a spac and have no adverse effect at all, it is just the luck of the draw.
If you feel better to have them on then I would use them. I would not buy them specially just for this trip. However if you plan to use them travelling to events then there is no harm in getting them now.
And yes the bell boots are a good idea, after all that ramble. LOL One pair of weatherbeeta shipping boots actually cover the hoof so bell boots are not needed. If I use my shorter ones (we call them floating boots ;-) like your showing then I use bell boots on the front feet. Horses often cope better with those shorter boot and the big long ones can cause some horses issues.
Make sure you ask the people if he has worn them. Because if he is uncomfortable about them it may cause more harm than good. I always ask them how they "normally" travel and take that into account. I guess from all of the above I'm saying one size does not fit all. If you put them on and he gets upset and hoping about, take them back off. I did see a horse who was loaded on his first time wearing them and the boot slipped, he panicked causing all types of damage to his owners float and himself.
Although one last horror story ;-) There was a woman locally who was on her way to the races and had nothing on the horses legs. The horse stripped his back leg and was bleeding out in the float. We were all out in the truck area unloading our horses when she arrived. We saw her drive past slowly with a trail of blood coming out of the float and seemingly no horse. We ran up to help and she wondered what the fuss was about until she saw her horse collapsed inside. They could not save him.
Hope your not eating! He will be fine. Just trust you instincts on Pitaya when you meet him. Even put him on a float at the end of the first ride if you like him. See how he handles it and observe him.......