Oxstrin Optimized - has anyone used this?

Hello - I just went to order my Cosequin for Crash and there was an offer for a free vitamin supplement: Oxstrin Optimized for Cats. I was wondering if anyone thinks this amount of wheat gluten or anything else in it might affect an OTJ kitty? Thanks for any input, especially from any users of the product.

BTW - Crash is doing really well. Momma bean has just been so overwhelmed with work that she can't visit here very often anymore We miss you all!!

Here's what the website says about it:

Oxstrin Optimized For Cats provides the antioxidants, vitamins and beta-carotene your cat needs for a strong, healthy immune system and overall health. Helps strengthen bones, support the renal system and helps alleviate the stress related to obesity and chronic health conditions.

Product Details:
Administration: Adult cats - give 1 capsule daily. Open capsule, sprinkle on food. Follow with water or food.

Active Ingredients:
Melon extract, hydroxylpropyl methylcellulose, cellulose, d-alpha tocopheryl acetate, niacinamide, natural chicken flavor, beta carotene, calcium pantothenate, wheat gluten, magnesium stearate, riboflavin, titanium, dioxide, pyridoxine hydrochloride, FD&C BlueNo. 1, thiamine mononitrate, vitamin A acetate, FD&C Red No. 3, menadione sodium bisulfite complex, FD&C Red No. 40, folic acid, biotin, vitamin B12, and vitamin D3 supplement.

Ingredients:
Melon extract (standardized to contain 100 IU of superoxide dismutase)
vitamin A 1500 IU niacin 7.7 kg
vitamin D 30 IU pyridoxine 0.9 mg
vitamin E 11 IU folic acid 80 mcg
vitamin K 0.1 mg biotin 50 mcg
thiamine 0.6 mg vitamin B12 3mcg
riboflavin 1.5 mg beta carotene 3.8 mg
pantothenic acid 3.1 mg