I travel from Birmingham to Berlin about once every two months to visit my friend. Due to the lack of airline choice on this particular route I chose Lufthansa who are the only airline offering direct flights between the two airports.

Price.
As you would expect from a charter airline Lufthansa ticket prices aren't to be had at a rock bottom price.
The cheapest I've paid is £106 return and the most expensive was £150. Prices don't seem to differ much month by month it seems to depend mostly on the day of travel.

Service.
Lufthansa have an easy to use website where you can check in and choose your seat for no extra charge. Boarding passes can be printed at home, emailed to your phone, or collected at the airport either by using the machine or check in staff .If you're an iPhone user boarding passes can be added to your passbook app which I have used twice and it works very well, when ever the boarding pass is needed you simply scan the screen on your phone, one less piece of paper to loose.
A selection of German and English newspapers are available at the gate free of charge which is a small token but it helps pass the time once on board.
The route that I fly has always been serviced by an Airbus A319 all of which have had nice modern interiors and a fair amount of legroom (I'm 6.1.)
Lunch onboard is included in the ticket price generally there are two choices, a meat or cheese sandwich, fruit or cake, chocolate and a mint. All of which are small but tastes good especially the salami sandwich!
Drinks are also included with a choice of wine, beer, coffee, tea and soft drinks.
The cabin crew can be hit or miss as I suppose with any airline. Sometimes the staff can be a little cold and unfriendly. I've never experienced a great level of cabin crew service on my flights, compared to BA, Monarch, Fly Be and last of all KLM who I used to fly with regularly, they have fantastic service.
Punctuality is spot on generally I've arrived early at our destination and have never been late or delayed.

Overall they are a dependable airline (if you don't get caught up in the numerous strikes), prices are in line with most charter airlines sadly cabin service isn't.