Sage Bambino Plus bean choice (Velo Tandem?)

JMcL

I've had a Bambino Plus with the Sage Grinder Pro for coming up on a year now, and having struggled for quite a while, I'm now getting decent enough results using Slumberjack beans. My main issue earlier was grind size - I was just grinding too finely. The result was at worst sharp and nasty, at best tolerable. With a coarser grind (14-15) for about 11 seconds (sorry, I haven't weighed the result in a while so not sure what the dose is exactly - but it looks to be about the right level on the double - single walled - basket)

So while the results are grand with Slumberjack, I'm wondering has anybody got anything drinkable using the Velo beans? I bought the grinder from Velo and they included a couple of bags of tandem, but the results were uniformly nasty - I ground my way through both bags on a range of settings (I was weighing the dose and output here) to no avail. Now, I'll hold my hands up and admit this was probably down to my incompetence at the time, but, while I could do the obvious and just go buy some, I'm curious as to whether anybody has a ballpark grind/dose setting for these beans. They're attractive as an option as I have an Aldi a few minutes away which almost always stocks them. I have read somewhere that the Bambino favours darker roasts, probably due to the temperature not being adjustable, but curious all the same.

I've also tried locally roasted beans - they're a fairly light roast which I know can give good results from local coffee shops that use them - but ended up with sour shots from those as well from the Bambino