You don't have to have your horse scoped, if your Vet firmly believes that the signs are ulcers.
I used Gastro with Nelson when he was diagnosed in January, and it worked well. After the innitial care of his ulcers, I got Nelson on 2 of SmartPak's products. SmartDigest Ultra from SmartPak Equine
Nelson had a massive colic due to the combination of stress while being on stall rest, the ulcers and the meds he was on due to the cause of his stall rest - and my Vet highly suggested that I get Nelson started on a Digestive Suppliment, so that's why I got him on Smart Digest Ultra.
And due to his Ulcers, I got him on another SmartPak Suppliment: SmartGut Pellets from SmartPak Equine
I suggest you call SmartPak directly, and explain to the Consultant that you get exactly what you described to us here. And they will suggest suppliments that will benefit your horses digestive tract and tummy.
They are great, and they aren't pushy on products. Just say that you aren't looking to buy right now, but need advice and help in what direction to approach.
I didn't see the last part of your post where you said he is currently on Smart Digest Ultra - so my appologies.
I would get him on Smart Gut - talk to SmartPak and see what they say about Succeed in compareson. And ask them their opinion on the matter - whether you should go to Succeed and drop Smart Digest Ultra. They are very educated on the suppliments that they sell.
I have to say, I am very happy with what I have Nelson on.