Good to hear you have had positive experience with the Valkyrie.
Found G&G very decent at lighter weight (0.25 & 0.28g), had a few jams with their grey 0.30g. Found Geoffs to be reliable feeders at the various weights I have tried (most recently 0.32g).
Have a few bags of Airsoft Surgeon in 0.30g weight on the way, will be curious as to how they perform. Haven't tried the brand before.