Well I went to REI last night to buy the needed parts of my pending bike tour around PA. Brought a 40+ mummy style (kilo flash, long) sleeping bag purely on the clerks reccomendation and extreme lightness. Took that and all the other "stuff" I brought back home, set up the Tent (T2 quarter dome), inflated the mattress pad (REI) and moved in for a test night. It only took about five minutes before I discovered that me and mummy style sleeping bags were not to be. I imagine if it had been -10F or even just 10F) I'd have been more than happy to sacrifice the straight-jacket affect as a trade off for the cocoon warmth of a mummy style sleeping bag. But it was ~48F last night and it will be in that general area, maybe lower, maybe higher, for my trip.
It also seemed that the bag was just not big enough across my chest. I'm not the biggest guy out there, but I do take an extra large size in bike jerseys, so maybe mummy bags are just designed small/snug. Any way I'll be taking it back today to exchange for a "flat" style bag that can function as a quilt as well. I'll probably exchange the mummy style pad for a regular rectangle one too. I know I'll pick up some extra weight, but sleeping comfort at night -vs- weight is a trade off I'm willing to make.