Do any RMIP runways exist that dont contain grass edges? I have been looking for runway pieces that just have concrete edges.
...no. The RMIP rwys are exactly those you find in the RMIP pack. Optionally, you can wait for the LMIP to be released.
Ace's new runways in RMIP-3 don't have grass on the edges. There is no grass at all, with or without the shoulder pieces.
We are working to release those "soon" ;)