DIY Gels with Cyclic Dextrin

I am currently training for a marathon in April and experimenting with different fuelling strategies. I am also making my own gels using the well established combination of maltodextrin and fructose in a 2:1 ratio. My understanding is the dual source of carbs utilises multiple pathways to allow for up to 90g/hours of absorbtion.

From researching different carb sources I have read that Highly branched cyclic dextrin is a relatively new and superior carbohydrate source to maltodextrin, allowing easier digestion and less of an insulin spike. The main downside is cost.

My belief as to why gel manufacturers continue to use maltodextrin is simply the lower cost. Making DIY gels is significantly cheaper so I am not fussed about cost of the ingredients.

My current recipe would be as follows

• HBCD and fructose in a 2:1 ratio.
• Electrolyte powder. Adjusted for expected sweat rate.
• Water
• Pectin

I hope to create an easy to drink and digest mega gel with 120g of carbs in a soft flask. I can sip this throughout the marathon and top up the carbs with powerade at the aid stations.

Has anyone here experimented with cyclic dextrin, specifically during longer races? Have I missed any downsides?