Cheap summer inslutation: large foam pad or MYOG underquilt?

[Macchina]

I recently hung in weather that go down to about 50 degrees F at night. I brought a MYOG fleece underquilt and it wasn't quite enough... Since the wife has taken a liking to my Blackbird (and my 900 fill down underquilt) I am looking for cheap options for warmth during summer hangs.

Option A:
I've seen people with huge pieces (covers entire underside) of thin foam in single layer hammocks and I'm wondering if that keeps you warm enough? How do you pack a piece of foam like that? Is an inflatable pad (I have plenty) with SPE better?

Option B:
What is the going design for a somewhat compact (warm weather) MYOG underquilt now-a-days?

[canoebie]

I use a layer or two of Insultex between 2 breathable layers of nylon with channels and shock cord. I really like it for summer and as a supplement in winter to my 3/4 length down. Check out Scott's site at http://www.backwoodsdaydreamer.com/

He has easy to follow DIY designs for insultex UQ. He is out for a bit right now, but I have had very positive experience with him for DIY stuff. I have used 2 layers of insultex down to about 40 with great success. Just a thought. Good luck.