I tried a GBE in a slim the other day. Afterwards it looked like I hadn't shaved (as I have fairly light skin but dark dark hair, so there was a dark beard showing under the skin homer simpson style straight after the shave), looked worse than was it was though, OK shave but nothing near SE shave quality.
Yesterday switched razor to a red tip SS. Shave was way way better, looked shaved, felt shaved. Mind you GBEs can be like this. They feel like nothing special on the first or second shave, but they have been the only DE blade I know that get better, and last for 6 shaves. Feels weird though, a SE can rip you to shreds and you'll know it, a DE will and you find out later, much later sometimes.
But anyway, fun times with a slim, a red tip, a GBE, the semogue SOC and MFW