DS45 has a stiffer base then the TT30 or the RK30 but next season they change the Highback to the new alpha high back on the DS30(was DS45 but they soften the base). Look for the DMCC light for a stiffer jump and freestyle binding. Plus the higher end bindings will have a new alpha footbed.
For straight park look at RK30
Jumps and park look at DS30
Stiff freestyle bindings look at the DMCC light that is coming out for next season.