What I do is basically use Pos (or similar), Copy and Delete.

So if it's a line like this:

Bleh=40, 40, 40, 400

I do this:

Get the position of the first ,.
Copy everything beforehand.
Remove everything beforehand.
Rinse and repeat.

Dunno if it's the best/fastest method but it seemed pretty quick for my from my tests (compared to other methods and using other functions).

Faster than Q_Strings too.