It is now generally accepted that the description of solitons in a classical easy-plane ferromagnetic chain in terms of a sine-Gordon theory is inadequate. The structural and dynamic properties of these solitons are not very clear. The authors present here results of a numerical simulation of the dynamics of a single soliton as well as collisions between a soliton-antisoliton pair. The dynamics of a single soliton appears to be consistent with variational method calculations. The energy dispersion E(u), where u is the propagation velocity, consists of three continuously connected branches. Only the first branch is sine-Gordon-like with an effective soliton mass. A soliton-antisoliton pair collision leads to a variety of final states. As a function of magnetic field B, there are four major regimes. At very low fields, the pair transmit through each other similar to a pair collision for true sine-Gordon solitons. For somewhat higher fields, the pair forms a bound state (breather mode) on collision. Further increase in magnetic field leads to reflection of the soliton-antisoliton pair. As a function of increasing collision velocity usG for an initial sine-Gordon pair, the various critical fields in general decrease. Furthermore, there are details in the final state diagram (in the usG-B plane) that correspond to resonance scattering (for breather modes) and branch transfer (in the pair collision leading to reflection). Implications of these results for quasi-one-dimensional ferromagnets such as CsNiF3 and CHAB ((C6H11NH3)CuBr3) are suggested. In particular, they suggest that non-linear elementary excitations in these chains may be breathers rather than isolated solitons.