I have shot at the following ranges and will post my opinion below: Iron sights, South Bay rod and gun, Escondido fish and game (trap only), Project 2000, American shooting center, and whatever the range used to be called in Escondido just northeast of the Ford dealer (been closed for years).
Iron sights is my favorite range to shoot pistols. I always request to shoot on the pistol side as most of the new shooters end up being sent to the rifle side. The prices are reasonable and they have the best selection of rental guns in SD. They do get busy on Fridays and Saturdays between 6-8pm so get there early if possible.
South Bay rod and gun is where I do all my rifle shooting. I liked this range so much I became a member and so did all my shooting buddies. If you want to join a range you will be hard pressed to find a better one in SD. They do have a single trap range but have limited hours because only a couple of R.S.O.'s are certified to operate that range (my girlfriends father just became an R.O. and found out for me). They have a pistol range, 100 meter range, and the main range (50, 100, 200, & 300 yards). Yes this place is way out of the way but in reality it isn't too much further than P2K. This is not a range for people looking to rent a gun as there are no firearms to rent.
Escondido fish and game is another great range. The down side is the wait to become a member here takes years of waiting. Don't fret though as they have public trap shooting two days a week. I have not shot at their pistol, rifle, or archery ranges but they look nice. The rifle range is limited to 150 yards which is kind of a bummer for me. Anyway, I have shot many rounds of trap here. The R.O.'s have always been friendly and so have the shooters I have encountered. Again this is a gun owner range so skip the drive if you are looking to rent.
P2K is a decent range but there are a couple of things I really can't stand about this place. One their prices are high for the experience. Look at the great deal you get by becoming a member... A couple of bucks off per hour of shooting... I will sum it up and say I have spent more shooting at P2K in one day than a year membership at SBR&G. Yes they have a nice 100 yard indoor rifle range but it gets old having to stop and clear your guns every 30 minutes so you can put another target up. I know they have been talking about finishing the dividing wall between the pistol and rifle side for only like 6-7 years now... Probably longer but my only prior trip there was before they had the store and you paid for trap tickets at a little shack. Ok I like the idea that people renting guns should be tested before handling any firearms but if I bring a mobile armory with me to the range don't you think I know what I am doing and forcing me to go shoot a couple of rounds at 25 yards is just wasting my ammo. Finally the good part of this range... They do have nice trap and 5 stand ranges. The prices aren't as good as EF&G but normally things are run decently with only two trips there that pissed me off enough I just packed my stuff away and left. I still have two tickets for 5 stand that have been in my toolbox for the last 2 years.
American shooting center was ok the two times I actually shot there years ago. The last time I went there to try to shoot was probably 4 years ago and after waiting for 2 hours early Sunday morning I vowed to never attempt to shoot there again. I know quite a few people have had really crappy service there and I have never had a bad experience shopping for guns there. I just don't shop for guns there as the prices are higher than a few other gun shops I frequent. The whole members get lane priority is bullwhip to me. In my opinion it is a good way to turn people away from your range. Oh well there really isn't much else for me to say about them.
I have not shot at discount gun mart but after the poor experiences looking at guns at the Morena location I don't care to bother with the drive to even look for anything there. I will say the workers at the Santee location seem a lot more friendly but there really isn't a large selection of anything in there.
So to summarize... If you are looking to shoot pistols for the first time Iron Sights is worth the drive. If you own guns check out SBR&G. Looking to shoot some trap Escondido fish and game is the place.