I don't think I was very clear.
I don't have a problem paying for Sierra, as you say it's very cheap, but I'd need to pay a lot more for the mytrack datafeed.
I don't want to commit to that yet as I'm already paying for another feed.
Also I won't get the historical data I'm looking for - I think they only go back about 2 weeks and I want to go back further than that.
Once I've got that, I can decide which feeds I need to pay for.
o