yes, s.d. is very good. dr. greenthumb has some awesome and distinctive strains too and is based in canada...klozit king is also in canada and handles the 'bc strains'. heavens stairway is good, also in canada (owns and operates overgrow too) and has similar selection as seeds direct but costs a bit more and is a tad slower...

all 4 mentioned above have been around for many years and are honest and reliable...
for sativa's, i usually go with dr greenthumb.