You are definitely on the right track - a 4000 cu. in. +/- pack is extraordinarily versatile for longer trips and situations. There are many good brands out there, meaning that their products are well made and will stand up to unreasonable use and punishment. The trick is choosing among the many competing offerings. I can only suggest that you shop until you drop - go to stores, fondle the merchandise, and try the pack on WITH A LOAD, and walk around a bit. I believe that the product evaluations in Backpacker magazine are reasonably unbiased. If you read these, you will see that personal preference due to different body types is very important.<br><br>Right now the buzz in backpacks is "ultralight," which makes sense for many applications. If price is no problem, you might want to check out Kelty's "Cloud" series, ultralight packs fashioned from spectra cloth. I believe the"White Cloud" model is about $600, but it weighs well under two pounds (I am qouting from memory here, so these numbers may be little off).<br><br>There are lots and lots of packs available, just go for the beels and whistles that are important to you. I personally don't like an integral daypack, but use a Lowe "Summit Attack" that is a nice daypack and serves as a stuff sack on the approach.<br><br>