either way will work. In the sink, it may take longer but you can still do it that way. At the laundromat, since those washers are front-load, you won't be able to stop the washer and check them mid-cycle, but it will certainly felt them. You won't have as much control to be able to stop the felting process when you choose since they will have to go the whole cycle. It's possible it might still need 2 cycles.
Mirl56 at Ravelry, too.
Learn from the mistakes of others. You canít live long enough to make them all yourself. Eleanor Roosevelt
Lady Feb Sweater
more shawlettes, socks