Welcome to our forum.
Congrats on the new spa! The Sovereign is a great tub. I agree, $650 sounds like a great price for the electrical work. As far a operating costs go, we are up in the U.P. and with our HotSpring Aria, which is used daily for 30-45 minutes a day, our bill is up about $35/month in the winter and pennies in the summer (we don't notice an increase). You've got a great spa, enjoy it!
FTR, expect your first months electric bill to be really high simply because you are going to use the snot out of this puppy. Mine was over $100 higher than normal, but I am using the tub 2X daily typically and then you have associated drying costs on top of that. I am sure it will stabilize a lot lower over time, but the honeymoon period is apparently almost like it's namesake.
Im curious about what the dealer is telling you about the pillow light. I just bought a 2008 h/s jetsetter that has the same problem plus my dealer tells me that 2 other tubs that came to him on the same shipment as my tub have this problem. Even though i realize this light itself is not a huge deal i am still a little concerned about the repair procedure my dealer has described to me. He tells me they will have to pry a panel off & dig through the foam isulation to fix it. As i have stated on a previous post it does not appear the factory had to good of a inspection proscess for a time period base on mine & your experiance.
I live in Indianapolis and have a Hotspring Vanguard which is 400 gallons. The soverign holds 355 gallons so just slightly smaller. I use our tub 2-3 times per week year in the winter for probably 30-45 mins each time. When not in the tub I turn the temp down to 95 degrees. Then an hour or so before I want to use the tub I bump the temp up to 100-102 depending on what the outside temp is. The other night I was in when it was 10 degrees outside and I actually got too hot with the water set at 102.My electric bills in the winter are around $15-$20 higher than they were before we had the hottub. In the summer the hottub doesn't cost hardly anything to run but the electric bill stays about the same since we are running the A/C.Another thing you can do to offset the electric costs is to change out every lightbulb in your house with CFL's. I have done this and it does save a lot of electricity.You got a great deal on the electric install. I paid around $1000 for electric install which included a run of 60ft of wire. Another savings is realize that the brand of chemicals doesn't really matter. It's all marketing, just like generic drugs what matters is the active ingredients. I use the Dupont pool chemicals from Lowes. Even though they say Pool on them if you look at the active ingredients they are exactly the same as the Baqua Spa or Leisure Time products. I bought a 25lb container of Diclor at Lowes for $83.00 http://www.lowes.com/lowes/lkn?action=productDetail&productId=232445-23132-10039&lpage=none 25lb of diclor is going to last me probably 2-3 years. Once you get the hang of balancing your water you'll only need to use a capful of Chlorine after every use. If the tub is not used I only add chlorine every 3 days to make sure I keep the chlorine at the 1-3ppm level.Enjoy your hottub! You made a great choice in choosing Hotspring!