Blue Buffalo's Prescription Urinary Dry Food?

Hi everyone! First time to this subreddit and after trying and failing to find information online about Blue Buffalo's new rx W+U Grain free dry food, I thought I'd come here.

My initial situation isn't unique- I have a male 8 year old cat recovering from a recent urinary blockage so I have him on Hills C/D urinary care wet food. My unique issue is that I cannot afford to spend $245/month on a wet food-only diet, and the typical urinary dry foods are not an option.

"Why? Don't you care about your cat?"

My cat cannot keep any of them down! I suspect he has allergy or intolerance to corn gluten meal or wheat gluten, and that ingredient is unfortunately in literally every one of the big 3 urinary dry foods- Royal Canin, Purina, and Hills. He's had a sensitivity to foods his entire life, so I wasn't surprised when he immediately puked the Hills c/d dry food up. I just still wanted to try because I take his health very seriously.

Before the urinary scare, he was on a grain free fish-flavored dry food and Tiki cat wet food. That is NOT because I think I know better than veterinarians or because I'm a health nut- I tried so many different cat foods and grain free were the only kinds that didn't make my cat vomit. At some point I had to decide between using the big-name brands and constantly cleaning up cat vomit (which definitely isn't good for him, either) or trying some of the other brands. Again, only grain free gave me some relief but I'm not married to it for any other reason other than it's what I've found that works to reduce the vomiting to near 0.

I already plan on speaking to my vet about this food, but I'd love to hear what this sub knows about it. Have there been clinical trials? I saw a "coming soon" button on the Blue Buffalo website for more information, but has anyone spoken to their vet about it? Or does anyone have any advice for how I can prevent another urinary blockage without having to spend $245/month on the Hills wet food? Or any other urinary rx dry foods without those corn/wheat ingredients?

Please be kind- I have been in and out of vet offices for the past two weeks having the worst experience with his recovery, and have been through the ringer. I've spent thousands of dollars already in the last month alone, and am trying to find the best path forward. Thank you in advance!