The platinum was special for several reasons. I hand selected every part that went into each one and used some special parts that I don't typically use. They were also tuned different in a few ways from the standards. To this day, the Platinum is one of the greatest mods I have ever offered IMHO.
The regular model won't have the switch for adding an extra gain stage and is tuned differently from the Platinum (a touch thicker and more saturated). I also make a custom 59RR that replaces the Diode Clip with the additional gain stage switch for an extra $20. It too is a touch thicker than the Platinum, but less compressed than the standard.
Feel free to email me with any questions.
Rob