I've had both (well not the spinal tap cos thats something completely different, but I know what you are referring to) but I have had a spinal and an epidural.

I didn't like the epidural, I felt that it lasted for longer than the spinal did and I wasn't able to hold DD1 for ages because I was just so out of it, had hardly any feeling. Also got really bad muscular pain between my neck and shoulder, which is a side effect of them.

Spinal I had with DS (I thought it was the other way round, but DH assures me that it wasn't) because for some reason I couldn't have the epidural, he couldn't get it in the right spot, so I had the spinal.

Oh, I also had more blood pressure problems during the c-section with DD1 than DS - which I'm told was because of the epidural. Also hated something sticking out of my back and it took the midwives to the next day to take it out.