Hills CD- any sensible alternatives?

[topbannana]

TopCat has had a couple of episodes of bladder crystals. These have provided him with yet another exciting opportunity for death involved hospitalistion for several days.
After the first episode he was put on Hills CD then after a period of time his urine was tested and he was allowed back on his old food. A second recurrence saw him back on the CD, this time for life (I cannot find anything in the literature that suggests CD is suitable for lifelong treatment but the vet assures me its fine)
The CD is £15 for a small bag, not an issue if he really needs it. However he will only eat fish flavours and the CD only comes in a low calorie chicken or full fat fish or chicken. In the summer he is always out and about and could be described as a healthy weight, certainly not wanting to put anymore weight on but OK. In the winter he undertakes a sort of feline hibernation and piles the pounds on, much to the vets distress.
He is genuinely not given anything else except the CD and we are very strict with DS about giving him treats or scraps.
I have recently lost a week long battle of wills over a bag of low calorie chicken CD. He eventually deigned to eat a few mouthfuls of it but it transpires he has been eating the neighbours cats food instead
So can anyone advise on an alternative? My options so far are:

1. Continue on fish flavour CD and acknowledge that he will get fat in the winter? I also fear this will get worse as he gets older.
   
2. Persevere with the low calorie version? This will help his weight but if he is eating next doors Felix or GoCat instead then it is putting him at greater risk of further bladder stones and rendering the vast amount of money the CD costs a waste.
   
3. Try something else and if so what?
   

Any advice or experiences much appreciated :)

[Lonecatwithkitten]

The RCW Urinary is a lot more palatable than c-d is and many cats that won't eat c-d will eat the RCW food.

[topbannana]

Thanks lonecat :)
Is RCW Royale Canin? The vet did mention that as a possibility but they do not do a low-cal fish and she did not mention the low-cal chicken may be more palatable.

[miggy]

the hills nutritionists have previously said that you can feed R/D (reducing diet) instead.Might be worth getting your vet to call the helpline?

[Lonecatwithkitten]

R/d is even less palatable than c/d as it is a reducing diet. So cat is less likely to eat it.

[topbannana]

Fat but fussy, who would credit it?! :o
Will chat with the vet again and perhaps give Royale Canin a bash :)

[PipkinsPal]

I have a bit of the same problem with my cat. Barnaby is on Hills CD wet (supposidly) but his brother, Troy, is on Hills ordinary biscuits. It is a real battle getting Barnaby to eat his food. I have bought Hills CD biscuits and give them to him on alternate days, or when he nags. I put about 5 of the Hills ordinary biscuits into his food to try and fool him. This sometimes works as Barnaby is a bit dim. I've even caught him hoovering up the biscuit crumbs in Troy's bowl. My vet hasn't said anything about getting his urine re-tested to see if he still has crystals or not. The vet told me he needs to be on Cystophan, 2 tabs daily, for life.