New sleeping bag time?

[BreninBeener]

I have recently been camping when it has been frosty overnight. My bivi bag was frozen on the outside and some on the inside surface too.

I used an Exped Synmat ul7 mat and an ME dewline bag. I was cold even with a hat and an OMM down gilet on, and didnt sleep well. The bag lofts well and has about 300g of down and weighs 667g.

I also have a Rab module 100 quilt which i am just a bit wriggly to use, but i guess i could use it with the Dewline if i was in a tent and not the bivi bag.

I also have a v warm Rab down bag with a huge amount of loft that weighs 1250g . This was my alpine trips bag, this is a big thing though and would be v greedy for space on a bike packing trip.

Im after a recommendadion for a bag (preferably ME as i can get a deal there) that will be a bit warmer than the Dewline. Im not tied exclusively to ME, but it does make sense. Im probably getting a tapered Synmat Winterlite mat shortly, as my rectagular synmat ul7 causes oroblems in my tapered bivi bag.

Any recommendations gratefully received.

Thanks

Ian

[Bearbonesnorm]

I've limited experience of ME bags but I generally work on needing 600g of quality down in a bag for sub-zero conditions, so the Helium 600 looks a good bet or maybe the Classic 500. I should say that I sleep cold.