With the C3 inks - you can create custom opaque mixes. You can choose different bases to create different effects while maintaining most pantone matches. You have A LOT of flexibility with the system. You do not have low cure..... The best you can currently get is 300*.
With the Rio system - you cure at 250*. Possibly lower... I would talk to a tech and give them your dryer situation - Wilflex (and most ink companies) is/are always conservative with their cure temps considering the wide range of dryers out there. Your ink opacity, is what it is - but its fairly opaque (for a RFU mixing system) I have been told. I will have a chance to play with it next month and get a better understanding of its in and outs.
All systems have formulas that are "close" but not quite right.... Also, remember all pms colors are checked on white fabric, not on a white plastisol base
.... I heard something about RIO having white plate type formulas, but I would have to double check that.
Currently in my shop - we do not use regular inks on any athletic wear. We use low cure inks (we use the C3 system and One Stroke ELTS inks - Used the One Stroke since before RIO came out). Its now the most reliable way to make sure we have not received any crappy polyester that will bite us in the ass.
What ink would you be using for your base white?