Suggestions for Digital Speedos for Series 2 that fits......

.... in the actual headset.
So, leading on from the Acewell speedo thread here viewtopic.php?f=10&t=2480 I thought it's worth exploring if there are others out there that will fit?
So, by that I mean one that doesnt involve cutting the headset etc like a vapor one would.
Additionally I want one that is fully digital, ie not like the sip ones that still need a cable for the actual speed.
Anyone know of any (other than the acewell) that can be used?
So, leading on from the Acewell speedo thread here viewtopic.php?f=10&t=2480 I thought it's worth exploring if there are others out there that will fit?
So, by that I mean one that doesnt involve cutting the headset etc like a vapor one would.
Additionally I want one that is fully digital, ie not like the sip ones that still need a cable for the actual speed.
Anyone know of any (other than the acewell) that can be used?