Hi Numnutz,
I can't respond from experience, because I haven't used the film yet, although I have plans to buy it too, but I have read an article discussing the Rollei IR film in 35mm format. Since I assume these use similar emulsions, from that article I can give you the following recommended list:
Yellow (#8): ISO 320 to 200
Dark yellow (#15): ISO 200
Yellow/green (#11): ISO 200 to 100
Orange (#21): ISO 200 to 100
Red (#25): ISO 100 to 50
Red (#29): ISO 25
Heliopan RG 645: ISO 25
Heliopan RG 665: ISO 25
Heliopan RG 695 (#89B): ISO 25
Heliopan RG 715 (#88A): ISO 25 to 12
Heliopan RG 780 (#87C) and higher: not recommended
In addition, the article warns against using the Infrarex black filter (RG3), due to it's spectral transmittance, it all but blocks the wave lengths necessary for capturing an image on the Rollie film (it is only useful for d****** work), while the Cokin (P007) and Heliopan (RG715) black filters CAN be used, as well as Infrarex RG1 and RG2 red filters.
Hope this is of some help...
Curious to see some of your results! Post some if you can!
Marco