No I haven't. Swimming lessons just weren't in the budget when either of my kids were babies. My ds is 6 and is going to his 3rd year of swimming lessons, but he just isn't really that keen on swimming, (no surprises there, I'm not keen on swimming either)
I am hoping to get my daughter some swimming lessons soon. She's 3, maybe for Christmas. (Christmas is in the middle of our Australian summer)
i wish I had but I started them when they were 3. Both kiddo's might swim/race for our town's team next year. It's a HUGE commitment and I'm not sure if I want to commit to it but we'll see