Remember some eyepieces are hard work. They are difficult or uncomfortabe on the eye.
Pretty much any Orthoscopic, and shorther focal length (under 15mm or so) Plossl's are like this.
Also, I've found that any eyepiece over 70 degrees and under $300 is likely to be rubbish.
At f8 you could go for something like the KK Erfle's
http://www.kkohki.com/English/kkohkiparts.html
or University Widescan 70's. Great eyepieces at comparitively good prices. I think these are the best bang for the buck.
http://www.universityoptics.com/125inch.html#70
I have a pair of the 20mm Widescan's, and they give eyepieces four times their price a run for their money.
I second Peter's recommendation of the Nag13T6, and I find the Nag9T6 is an awesome eyepiece.
The Panoptic's are fantastic, easy to use, and very comfortable to look through.
Cheers,
Jason.