I used BCAA's for a few years until I decided to go back to basics (i.e glucose/electrolytes/water). There were a few reasons why I did that, not least of which because the whole market of supplements is so poorly regulated that it is impossible to rely on advice when it comes to anything related to diabetes.
In terms of known brands, you may wish to consider Genetic Supplements. They make the best tasting BCAA I have tried and they seem to be more affiliated with professional athletes. One of their ambassadors is the T1D body builder Phil Graham, who you may have already heard of. However, be very weary about what you read and believe when it comes to terms like 'cyclic dextrin'. In our world of diabetes, if it does not raise BG's then it does not contain carbohydrates (assuming you're not on a LCHF diet or a high protein diet). The only way to know for sure what impact the solution contains is to blood test and gauge how you feel during and post-workout.
For weightlifters, BCAA is usually consumed as a soluble powder broken down in water as you would want to sip it throughout the workout. You may also wish to opt for Instant BCAA so that it doesn't congeal like whey.
I did not find I became more insulin resistant/sensitive on BCAA.
Hope that helps!