I haven't made jerky in years, but I seem to recall having good results with the cut that becomes London Broil which is usually flank steak or top round roast. It's lean enough to use directly without doing a lot of fat trimming and it slices well either with or across the grain depending on whether you want strong jerky or softer jerky. I usually go for the strong cut with the grain since I want my beef jerky to have some real chew to it. Hmm, I'll have to go get my dehydrator back from my brother and look for my old recipes. Homemade always beats anything mass produced and thrown into a plastic bag. I hear you on the plain version, but it doesn't hurt to add a little salt and pepper in there. Beef always gets better with both.