Normy,
I am a civil engineer in the water business. I also just replaced the pump on my pool and it made a huge difference. I can do the calcs for you if you need them as they are very straight forward.
I am extremely biased towards pentair pumps. I have had great success with these pumps in well over 250 hp applications on down to the pool pump I have now.
First of all the reason that I changed my perfectly operating old pentair single speed pump is because it is an energy burner. Advances in pump manufacture have contributed but not like the new motors. Pentair takes this to the extreme and for a very reasonable price considering the cost of electricity. I installed a variable speed, soft start Pentair and easily cut my electic bill in half, easily. Furthermore, when I did a cost analysis, the savings by converting (with a $200) rebate, had a cash payback of less than a year! This does not include the $100 I got for the old pump. I paid about $950 for the 3050( the lessor of the two pumps) and it runs like a champ. If I didn't have a solor heater I would save more by not having to pump the flow to my roof. However, I am thinking of getting an inexpensive blanket to reduce this expense futher.
Here are my choices (depending on the size of you pool):
http://www.pentairpool.com/products/products3.php?id=76
This brochure covers both the 3050 and SVRS. The SVRS is an incredible unit as well but my pool is pretty straight forward.
Let me know if you need the calcs. What I will need is the dimensions of your pool (close is good) and the highest elevation change in the system. In other words if you are going to have roof top solar collectors. If no roof top stuff, than I will assume that there is the normal seperation between the pool low point and the pump volute (engineering term, because we can throw around terms like that LOL).
Also, cost out the salt system, they are very expensive and can have long paybacks compaired to a floating distributer.
Make sure you calculate the filter size as well. This is a critical match because if the filter is too small you will not be able to turn the pool over without filter bridging (not working). What type of filter are you going to use, make and model.
The normal calc involves the pool turnover. Once per day is adequate, but the general rule of thumb is twice. I have found that pool men will tell you that you must run the thing 6 or 8 hours per day and that is just BS. My pool man, who I no longer have, was somewhat of an a$$ about this. I run the pool pump and filter for 2 hours. Man did he listen when he saw that the water condition was actually easier to maintain.
Anyway let me know.
Also, I have a perfectly good Kreepy Krauly that I recently replace with a new one from a garage sale that I will let go cheap if you are interested. It is in PERFECT operating condition, a little bleached out but it runs as good as a new one.