I have a pair of TA's and love them. When I was researching it there was something about the width of the booth that was different between the TA and SRS - I think the TA's are a slightly wider fit.
I have a pair of the Crossfire SRS. The fit me very well. They are a little narrow and tight new but after 2 rides they formed to my feet very well. Fantastic support around the ankle. The SRS is neat as you can change to the enduro soles and back if you wish. My pegs do scratch up one of the bolt heads in the arch and this may be a problem when it comes time to remove it. I believe the toe height is a little higher on the SRS. I did not have to move my shifter but I did notice it but only for the first few shifts. I got a really good deal on last years SRS but if paying full retail I probably would have went with the less expensive TAs and had them resoled when needed. After the 2nd resole the $ will be the same. Revzilla has the SRS on close out very limited sizes for $319
I have 11.5(US) EEE foot and the sidi ta are the most comfortable boot I have had. I love them. Very well made.
Love my Sidi TA boots. I chose them for the reason Micfasto mentioned, the lower toe box. I did find, however, that it's easy to catch the edge of the inside hinge cover on a footpeg. I was kind of disappointed that I lost one hinge cover after a couple of rides. I would definitely buy them again, if need be.
went with the ta's. wear size 11 street shoes but ordered the metric 46. hope there not too big. then again I'm used to flopping around in size 12 quadrants.
That is one reason I also went with the Sidi is it falls in the 1/2 sizes and fits me well, where most other boots are a 1/2 size big or small on me.