This strongly depends on the packs itself but 100MB is very limited to store complete packs. To give you an idea, please find below some example sizes below. These are the sizes for SX700 packs from Yamaha. It might be that there a specific versions for SX600 with lower size. Note that commercial packs are often (much) larger.
Johan
African 25
BestOfEurope 67
Brazilian 43
Celtic 44
China 13
ChurchChristmas 64
Entertainer 75
EuroDance 40
Europe 75
Italy V2 106
Latin America 40
Mexican 8
Oriental 76
Romance Latino 26
Romenia 65