Not aggressive. Anything but aggressive at least when smaller/growout. In fact I would setup a tank just for them to grow them out as they can be picked on quite easily by other fish that are even semi-aggressive..
Pima are selling extrememly fast. Please call me if you would like to order them. Shipping charge can be estimated by going to http://postcalc.usps.gov putting in your zip (our zip is 92867) Single fish packing will be 9lbs. Two fish up to 5 will be 13lbs give or take 1 lbs. Box dimension is 16" x16" x 12". We do not charge extra for heat pack or boxes, or oxygen. You pay for actual shipping cost. UPS, FEDex and DHL will be double what USPS charge.
Pima actually will do much better in a group. They will be less shy and more willing to feed on worm, feeder, shrimp, etc. They are not aggressive towards each other.