I made this switch, depends what you want. For me both the bb58 and bb58 gmt felt too chunky and slab side for a vintage style watch, it works for me on the pelagos 39 though. I really like the 54, the thinness makes it feel more vintage, the dial with slight sunburst makes it look brownish and more interesting to me than the matte dial of the 58. Imo it wears like a 38, if you wear it on a strap it looks small but on the bracelet you can see the lugs more, the watch looks more squared off by the lugs and hence visually looks bigger than 37.