Thanx for the advice..I`ve researched it a bit and chain fires are bad JU-JU to say the least, be like holding a hand grenadeNever owned one but my Ex father-in-law (Bill) had both when he belonged to the NSSA. If'n it were me, I would prefer the revolver with the Top Strap. Looks to be a stronger frame. Plus the one w/o the top strap is held together with only a wedge. If the wedge gets worn, everything loosens up including the cylinder to barrel alignment. Not the case with the Top Strap Model.
Another concern, with either style, is cylinder chain fire. Bill used Crisco on top on each ball to seal the cylinder and prevent the cross ignition.
I would also buy the Stainless Steel Model for ease of cleaning and prevent rust while it is stored away.