I have the restrap bar bag and had the same issue with the buckles. I contacted Restrap and they were very
helpful and informed me that the buckles needed respositing on the strap so they sit flat against the bars. This makes it a lot easier to use.

I do agree that the bag would be even better if the straps weren’t sewn in place and could be moved to different positions.

Other than that it’s been great.

If you are a tight-wad like me then a do a search for molle pouch on ebay, get slightly creative and save yourself a fortune.

Have you tried the Lifeline seat pack on a dropper post, it’s only got a single post strap so might work well, if it does it’s an absolute bargain