When parking I always try to back in if I cannot pull straight through and width wise I can fit into any space a SRW can, albeit its a little tight. I usually park in the back away from people anyway even with my Odyssey.
One thing I hate and will get extenders is checking the duals tire pressure almost impossible.
Mileage wise my F350 SRW got 3 mpg better not towing but the same towing. I'm guessing this is mainly due to gearing and emissions crap.
Drive thrus I can fit but usually don't as I'd rather go inside and sit down. One lesson I have learned is don't try pulling a 40' fiver through McDonalds at lunch time.
I will always own a dually from now on. The stability is amazing and I feel more secure than I did with my SRW.