I tried playing on the Medeli e-drums yesterday at TMS. Sad to say (and I'm just being honest), mas maganda pa rin talaga ang Roland e-drums. Sa construction and feel, sa sound, roland pa din talaga.
You mentioned about the expansion card (or additional sounds) of TD-10 , I suggest na wag ka na kumuha kung meron man. What you should try is Drum VST na lang like toontrack's SUPERIOR DRUMMER 2 and fxpansion's BFD. Ang layo ng samples nito compared to the Roland samples (or any other drums samples available).
My current setup is a Roland TD 3KW and Superior Drummer 2.