Ready to buy if route makes sense

I appreciate the responses thus far and for the most part they have assuaged my fears of low (for a Prius) mpg. To answer some of the questions:

1. Charging is not an option at work. We have to park pretty far away from the building. Perhaps someday there will be front-row charging stations. For my commute a BEV, PiP or Volt would be ideal. However...
2. I have driven both the Volt and the PiP. I don't want to turn this into a Volt vs. PiP vs. Gen III debate, but the PiP is $6k more than a comparable Gen III Five ($33k vs. $39k) and the Volt is another $6k on top of that ($33 vs. $45k). The $2500 (PiP) and $7500 (Volt) tax credits will not help me out based on the Form 8936 and my Form 1040 estimated taxes for 2012. We simply have too many deductions as a young family with a mortgage.
3. Regarding the "payback period", I understand what you are saying. I should have said that I am looking to see if the more expensive PiP or Volt are actually equal (or cheaper) over a 10 year period than a comparable Prius. To the best of my knowledge and ability to find data online, unless gasoline rises to >$7/gal and stays there, then the regular Prius wins over that period.

Don't worry about engine or inverter temp. The Prius will take care of itself. If you are going 25mph you'll discharge the battery within 2 miles. The ICE will start (or keep) running to charge the battery. I would expect at least mid 40's mpg depending on the traffic, weather & your driving habits.

Batteries are expensive. Gasoline isn't. An EV or PHEV will have lower operating costs than a standard Prius but at last week's gas price ( $3.319/gallon and ~17.2c per kWh) the difference is around $1.25 per 100 miles.

Fair enough! Do you have an opportunity to rent a Prius (either from a Rental Car agency or calling your local Toyota dealership to see if they will rent one to you for a couple of days)?

My brother did just that (rental car, package 2) so he could get a feel for his commute (which involved a couple of short trips (< 2 miles) and a hilly drive (10 miles) to work, a short drive (2 miles) to swim at lunch, a short drive (2 miles) back to work and a hilly drive (10 miles) home. He averaged over 45 mpg and his commute was about as "unideal" as it gets.

Hi Hp, welcome to priuschat . From all the info. u have given, I have no doubt that u will reach your goal of mid 40 mpg. as a newby prius driver & will increase mileage as u learn the nuance of the car. Buy it, u won't regret it.

your mpg goal is realistic. I do mostly short trips (my commute is 4.2 miles) and mine stays good, it does get better if I drive further. there are things you learn when you drive the car how to get the max mpg from it. like my super short 4 mile drive, I can run the battery down as much as I want towards the end because when I leave work I have the mandatory warm up engine on period that can drop my MPG by as much as 11 before it shuts off and this is in 90 degree plus. so I might pull into my work at 70+ but will be in the high 50s low 60s after I restart. then you gotta work for those good mpgs again.

Technically, climbing hills isn't the problem, braking while going down the backside is what kills the mileage. If you can coast down the hill, (almost) all the energy spent going up the hill is returned in the form of speed.

I would be hoping for low to mid-fifties with a commute like that, with some care in driving style.

I'm a new Prius owner in the same area. My wife drives the car 95% inside of DC. It's only been about 2 weeks of ownership, but my wife is getting mid 40s. Although I'm working on her driving techniques and yesterday she said she had most of her small trips in the high 40s instead. I'll be monitoring it more to see what happens. Gotta sign up for Fuelly I guess, although I'm not sure my wife wants to help me with it when she fills up.

I drove the car out to Centreville from DC twice last week for work. 30 miles one way and car was great on 66. Since it's a reverse of most peoples commute it is very easy going to work, not a lot of traffic at all. I got over 55MPG on both drives out there. On the way home it was better, there's a lot of traffic from 4-6PM on 66 inside the beltway near the route 7, 29, and Glebe road exits. There I was able to put it on EV mode and keep it at the 100MPG mark. When getting home on those trips my MPG was over 60.

I think learning the good driving techniques and not getting worried about people who want to accelerate hard and drive quickly (even in the right lane) is the hardest part. There's not a lot of patience with the driver's in this area, but I've learned not to care.