This is exactly what I did with great success: I tried a pair of 11.5D shoes on the #5 last (like the Strand). Tried on the Strand in an 11.5D and found it too tight in the toe area but fine everywhere else. So, I ordered a pair of 11.5E Strands. I started wearing them right away because I really liked them. Low and behold they were too big on me and actually caused back pain. Ended up selling them on eBay for a loss. Later purchased a number of AE's on the #5 last (most recently the Strand) but now in a size 11E - not 11.5D. No pain at all and they fit wonderfully. Very, very small amount of heel slippage but overall they are working out very well. If you haven't worn your Strands yet outside I would encourage you to at least try on a 10.5E.