One potato, two potatoes?

Now that I've tried growing sweet potatoes, I'm ready to move on to the "other" potato. Potatoes provide more calories per square inch than any other crop, which is just one good reason to grow them. The other reason, is that I'd like to try to avoid the green tint that seems to plague most potatoes I buy at the grocery store. According to the County Cooperative Extension planting guide, you can plant potatoes NOW! 

 I put a call into Ronnigers Potato Seed Farm, and I asked them if they had any advice on growing potatoes in the Phoenix area, here's what they had to say:

There are several general guidelines to follow when choosing a potato variety for your climate. Potatoes need the soil temp to be at least 50 degrees or warmer in order to start sprouting and grow. Therefore, the earliest that we recommend you plant seed potatoes is two weeks before your last spring frost. Living in an area where it gets really warm, your goal is to harvest before the temps get into the mid 90’s or hotter. Often, what happens is the soil becomes too warm for the plant to produce tubers or put size on the existing tubers. If you have a spring month that is more rainy than another, you may want to again tailor your planting schedule. Freshly planted seed potatoes are susceptible to rotting in the ground if they receive a lot of moisture before emergence. Once the potato plant has emerged, consistent watering habits are needed. Potatoes like evenly moist soil and never really like to completely dry out. One pound of seed potatoes will plant approximately 10 row feet if you space the seed pieces one foot apart. One pound of fingerlings will plant approximately 15 row feet if you space the seed pieces one foot apart. When we plant, we do 36 inch wide rows with 12 inch centers. Potatoes need room to spread out and grow! The worst mistake that gardeners make is crowding. So, in your 4x8 bed, 2-3 pounds would be plenty. The seed potatoes that are the size of a golf ball or an egg, plant whole. Some of the other potatoes you will need to cut as long as you leave two eyes per piece. Planting depth, 3 inches.

These are the varieties that they recommened for this area.
Yukon Gold, Red Pontiac, Viking Red, Rio Colorado, Red LaSoda, Kipfel Fingerling, Ozette Fingerling and Purple Peruvian Fingerlings are all more heat tolerant. ( The Yukon and the Red Pontiac are early season. The rest are mid to late)Desiree and Nicola are a good choice for heavier clay type soils.
Just starting out, you may want to just stick with potatoes in the early season, that way you won’t have to worry about the heat factor and you’ll get a feel for growing potatoes.
I'll try the Purple fingerlings and Red Pontiac as my first choice as a potato farmer. I'm starting out small and using a potato "grow bag" because I'm completely out of garden space for the season.
If there are any gardeners that have had any experience growing potatoes, I'd love to hear from you!