Pappaslap:

There are streams there such as the Pecos, Santa Barbara, Rio Grande, Brazos, and so on, but none of them measure up to the San Juan. If I get within 8 hours of that river, I will go way out of my way to fish it. I can not imagine being in NM and passing over the SJ for the other waters. And May is a great month there, IMO. The river is the busiest in October, but May is my favorite because it is baetis time. You can wade a lot of water there, the quality water upstream of the Texas Hole is highly produtive, as is the Tex Hole from a boat, and then walk downstream.

It is not an easy river to just walk onto anc catch 50 fish a day with no prior experience. It is the type of place that you want to hire a guide to get you dialed in, and then fish it. The river is also very different from season to season, so what you did in the spring will not necessarily work in the fall. I would get a guide to walk you upstream early in the day, and then along 11:00 am when you get alot of baetis washing down into the Tex Hole, hop in the drif boat and fish it hard and then travel on downstream.

There will be some dry fly action in the afternoon as well.