Devo 7e and DSM2 CM621 and AR6100E receiver

I have been trying out these DSM2 receivers with the Devo7e but can't fly further than 30m. Beyond this distance the quad drops like a rock!
Has anyone tried any of these receivers with good distance?

Have you made the range mod to the 7E?

Nope.
But with a Walkera RX601 I can easily get 150m.

I have a CM621 that I haven't flown yet. I did range test it (on foot) with my Devo 7e w/o range mod and found that it was solid to over 100 yds LOS. I have an Orange RX with two antennas on long feed lines and it was a few yards better under the same conditions.

I get a solid 100 yds (clear LOS) on a quad with the Orange receiver having the antennas attached to the top edges of a carbon fiber top plate on cable ties at 45 degrees. I am concerned that the CM621 will not do as well with the antennas that can't be moved away from a carbon fiber frame.

I have some silver conductive ink in a hypodermic syringe from Banggood.com that I bought to fix the range problem, but I'm not currently in the mood to risk the only transmitter I have with a fairly delicate operation. Maybe when I start using the CM621, I'll take it on.