I found this old thread at CN:
https://www.cloudynights.com/topic/5...edge-2-vs-125/
A 1.25" wedge will heat up quicker due to smaller dissipation area so is recommended for smaller aperture telescopes. See post #6 in above link.
Not sure that Baader even make a 1.25" version. Lunt do. I have not been able to find light path lengths but normally a 1.25" diagonal path is considerably shorter than a 2" diagonal path and this would likely be the same with a solar prism wedge. You would be limited to smaller aperture viewing which a 76mm telescope would come under.
The recommendation from Baader though is not to place the Barlow in front of the wedge to avoid excessive heating of the Barlow (or Powermate) lens elements.