Hello fellows. Thanks for your comments. I don't have any illusions regarding the magnitude, or lack of magnitude as it were<g>, for the gearing change provided by dropping one tooth on the small ring. At the end of a big, climbing day, for example, it would just give me roughly an extra 2 rpm cushion, at my same, sometimes pathetic end of the day power output on the last climb, towards not falling below my self imposed, minimum 65 rpm cadence. However, this minute, though perhaps laughable<g>, change is not expensive. I am going to get a new ring regardless of whether it is a 38 or a 39, so I just wanted to know whether anyone has tried a 38/53 combination and noticed any shifting issues on the front chainrings while shifting from the 38 ring to 53 ring versus shifting from the 39 ring to 53 ring.

Though risking excellent DA shifting for a couple of lousy rpm sounds nutty, I might just try a 38T from another company, and if I subsequently notice any degradation in shifting on the front chainrings, just take it off and throw it in a box until such time I can match it up to a big brother ring from the same company and use the set on one of my other bikes that needs rings replaced. Then I would just get a new, 39T Ultegra ring that matches up to my big DA ring for the original bike in question.