Long term T1 here, Have had MANY "issues" with incompetent g.p's, especially with the current one, leading to the loss of a leg. So as you can imagine, I am NOT in favour of them, for any degree of diabetes related treatment. She was even made, by her practice, to go on a diabetes course (2 days ?) and is the practice's diabetes specialist, even though she's only there for 3 days each week. Suffice it to say, I run rings around her, on the few times I've needed to see her or anyone else there. Yes, she maybe okay for hangnail. etc, but... considering the number of diabetics, which is increasing expotentially, then training they receive(d) is woeful.
Anyway, have been on S.R. Metformin for maybe 12/15 years, dosage now 3 x 500's. The standard release version had the usual side effects, with me. The gen. practice, were quite resistant about me changing from 2 x 500's (the then recommended NICE dosage) to 3 x500's, but ever since I did, it had a very significant effect on my insulin resistance.
Since then, both of my insulins have changed, which has also had a similar effect & dosage has changed, i.e. been reduced as well. My hospitals, diabetes drug specialist, who has always been a fan of metformin, is very happy with the outcome & results.