My (very recent) experience with saltwaterfish.com is mixed; I ordered the following:
1 x Tomato Clown - Wild $12.99
1 x Pajama Cardinal - Limit is 1 $1.99
3 x Blue Reef Chromis $23.97
1 x Green Chromis - Limit is 1 $1.99
2 x Porcelain Crab $11.98
1 x Cerith Snail - Group of 10 $9.99
1 x Serpent Star $5.99
1 x Mushroom Polyp - Ricordea $5.99
1 x Lettuce Nudibranch - Limit is 1 $1.99
1 x Deep Sea Yellow $14.99
The pj cardinal did not survive the trip, nor did two of the blue chromis. The lettuce nudibranch survived a few hours but did not even start feeding, by the morning it appeared to dissolve when I picked it up. Fortunately my two original lettuce nudibranchs continue to do well. The green chromis did not survive over night (it arrived emaciated and extremely small, 1/2" maybe?).
Eleven Ceriths arrived instead of 10 and two weeks later all appear alive! The crabs seem to be doing well (even in the presence of three emerald crabs), the serpent star is doing well and is active even during the day. The yellow Gorgonian is a wonderful piece with very many spectacular hair-like polyps.
On balance, while satisfied with the order, I am appalled by the high shipping mortality rate. Their "guarantee" requires that one sends back the fish with six days of their shipping date and essentially receive credit toward your next purchase. If you want to get the "guarantee" honored immediately, i.e. not wait until your next order, then you have to pay for the shipping of the guaranteed stock. It costs nearly $30.
Now, in fairness, everything seemed pretty professionally packed.