Which premium characters do you think are the best?

Moleman.
http://i.imgur.com/F1wjjgF.png
I chuckle every time I see him, this is VERY beneficial to me.

If you haven't purchased Mystery Boxes until you open ones with Squeeky Voiced Teen and the Blue Haired lawyer I'd suggest that. Buying them with mystery boxes turns out to be cheaper than just buying them outright, it will also help your multiplier which will eventually make characters cheaper for you (through farming donuts).
Roscoe with the Ajax Steel Mill is a limited time premium character that you should watch out for then buy (hold off on doing any of his quests until you find out why, or it's a waste) ;)
Also if you play or can load your game on a iOS(apple) they often have deals on iTunes gift cards, so you can get a little discount on buying donuts with real money that way.

In the end it's up to you really which premium characters you want.

For starters, Terri and Sherri. One of the best in game duos, if they're every available to be used in an event, they'll be quite valuable.

Second, vegan protestor, Jesse grass. Once event only, now anyone can get him, tasks in all recycling depots, integral to any monorail owner.

Dr. Nick. Why?
Hi Dr Nick.

"someonewashere;c-1702462" wrote:
For starters, Terri and Sherri. One of the best in game duos, if they're every available to be used in an event, they'll be quite valuable.

Second, vegan protestor, Jesse grass. Once event only, now anyone can get him, tasks in all recycling depots, integral to any monorail owner.

Dr. Nick. Why?
Hi Dr Nick.

T&S almost ALWAYS involved in the Halloween&Christmas events too >:) o:)

Oooo Sherri and Terri especially when I think I got them in a mystery box.

Thanks guys, such a great insight. I appreciate that :)

Premium characters fall into 3 categories for me.
1) Characters you like. There are some characters you're just fond of regardless of cost or utility. They differ from player to player but there are certain characters people have to have in their Springfield. The value of the premium character in this instance is completely personal.

2) Useful characters. Some premium characters earn extra $ and XP on top of their premium status (like Sherri & Terri or The Wiccans), help with Springfield Heights (like Sideshow Mel & Moleman), or help with the rail yard for track pieces and donuts (like Jesse Grass, the Hippie, Dewey Largo, Uter, etc.).

3) Characters with multiplier items. Some characters come with decorations (and more recently buildings as well) that include a bonus percentage for your multiplier. Permanent premium characters like Chester Lampwick, Chester Dupree, & Frank Grimes all come with such decorations. Limited time characters like George Washington and Dwight D. Eisenhower also come with such decorations. More recently, Tapped Out has been releasing limited time characters with buildings that earn money & XP and also have a bonus percentage for your multiplier like Jaques and Senor DingDong.

I personally gravitate toward category 2 & 3 and only splurge on category 1 if there's a rebate.