The new steerable 3D multi-beam echo sounder system SEAPIX offers different operational modes to acquire supplementary information during the acquisition process. In this paper, we focused on 2 modes : the classical MBES mode and the longitudinal mode. The consistency of the data acquired from these two modes was verified through the evaluation of statistical features (mean, standard deviation, Kullback-Liebler divergence). Besides, the longitudinal mode also proposes a new date type : pixel-based data, which offers a complete backscatering profile for each pixel. A comparison of classification performance was perfomed with a sandard Bayesian method. The pixel-based date clearly outperformed the classical mode's data (93.36% vs. 50.65% using a level-based method and 81.5% using a profile-based method.