At 5mm, the only comparable eyepieces to the XO would be the TMB SMC and AP SPL.
I've had the SMC's and the eye relief is more generous than the XO. They don't work well in fast dobs, but will be nice in your refractor. The tiny 30 degree field of view did eventually get to me.
The AP SPL's are exceedingly hard to get hold of, and that fact alone virtually rules them out. They also have better eye relief, but the XO generally gets more favourable reviews.
I chose the 5 XO because it was easy to acquire and works well in all my scopes and I preferred it to my 5 TMB SMC.
So, I think you're back to where you started from.
