I got a 30mm UW when I bought my 8" Dob from Andrews. Although I can agree it may be a bit pricey for an eyepiece you will want to upgrade, it is still quite good.
I've always been happy with mine, although I tend to use a 20mm Televue Plossl mostly now. I still use the UW 30mm though.
I haven't got a Barlow, so can't help there sorry....
