I used tri-bars on LEL'09 so a barbag wouldn't have worked. Generally not a fan of them anyway.
I got by with jersey pockets, tri bag mounted just behind the stem and a rack pack.
I preferred my rack pack over my Carradice Barley (much as I love the Barley) as the latter is slower to open up and faff around in. Having more space (in the rack pack) meant it was easier to get things at the bottom of the bag too.
With the bag drops there's no real need to carry changes of clothes (unlike PBP if you're not planning on using Baxters or some other support system). I just rode LEL as a series of 300km or 400km rides between bag drops.
You can't do it this time (because of the route change) but I dumped a load of (overnight and emergency) stuff (at my risk and with controllers agreement) at the Eskdalemuir control and treated the Eskdalemuir->Dalkeith->Eskdalemuir section as nice daytime 200km ride. I think geraldc left his entire saddlebag at Eskdalemuir!
I did consider a bar bag for PBP'11 (since tri-bars are banned) but the Altura one I have got in the way of my lighting system (two B&M Ixons on a Minoura SpaceGrip) and I didn't have time to investigate other bags or other light mounting arrangements. The tri-bag worked fine for power pack for GPS and snacks (along with jersey pockets). Brevet card, wallet and 'phone sat in a side pocket of the rackpack. It took but a few seconds to get them out when stopping at each control.
LEL'09:
http://www.greenbank.org/audax/lel2009/IMG_0177.JPGPBP'11:
http://www.greenbank.org/audax/pbp_02.jpg(PBP luggage bigger as I had 3 changes of shorts/jersey/socks with me. The external tool saddle bag worked a treat too and saved space in the bigger bag.)