Found this place on accident when we arrived in Mirissa and our booked guest house had lost power. I was sick with food poisoning and we were just driving, looking for a good guesthouse, in the dark.
Samantha showed my friend the place, and offered us a break on an air-conditioned room that was open. Without any warning that we were coming, there were a few small bugs in the bathroom (this happens when you're in a tropical garden) that he washed away for us. A few other little issues popped up, but he promised to fix them in the morning, and he did. So accommodating.
Bed was really comfy, which I didn't find anywhere else in Sri Lanka. Gardens are gorgeous and quiet, but you're RIGHT across the street from the beach and right in the middle of everything you'd want in Mirissa. It's a small beach town without resorts, but I was so happy in this little beach house.
They didn't clean the room while we were there, but other than that things were great. Had to ask for more towels, etc. When they harvested coconuts Samantha cracked a few for us to enjoy on our little porch.
Only other thing to note is the curfew - gates are locked at 12, so unless you have a cell phone with which to call and wake up the owner, you can't get in. We ended up sleeping early, and there's not a huge party scene, but I think this would bother some people. It's for safety and makes sense, just something to know.
Would def come back here if I were going to Mirissa.