Is abdominoplasty versus panniculectomy better?

Very Different. The operations are very different. Tummy tuck operation typically involves excision of excess skin/adipose tissue, re approximation of abdominal wall muscles that may have spread with weight gain/loss or pregnancy, and sometimes liposuctioning. Panniculectomy, on the hand, involves ONLY removal of excess skin/adipose tissue of the lower abdominal wall; much less of an aesthetic outcome...
It Depends On Goals. A dermolipectomy, or panniculectomy, is a procedure that removes the excess apron of skin, but does not tighten the muscle. A tummy tuck also tightens the muscle. Which is "better" depends on your specific case and objectives. Be sure to consult with a board certified plastic surgeon to discuss your goals and get specific advice.
Who is doing ? Abdominoplasty includes besides resection of excessive abdominal fat fold , tightening and reconstruction of weak abdominal wall usually don by plastic surgeons , ( usually not covered by insurance as it is cosmetic procedure ) . Panniculectomy done by general surgeons for recurrent infections of the fold not considered as cosmetic ( usually insurance covers it ).