I too like the way Dan is moving with the quality kits, but are we so gullible that £2.50 is really an issue here Jim. Are we so tight that the price of 1 pint of beer makes us buying pens out of reach for Joe public?
I agree with Neil, he nends to price his pens right or they won't sell, however does £2.50 on the price of a pen really stop you selling a pen with an increase of £2.50. Or is it that you expect more of a premium back because they are quality kits.?
I know the answer by the way.. 
What do you class as reasonable priced Jim? Your reasonable price and mine may be totally different. I believe that £10 per kit is reasonable..
All in all its what we all expect to pay, but remember I would sooner be known for quality pens at a good price rather than for supplying cheap pens.
But don't forget it's only £2.50 that's at stake here.. sorry it might be, wow, that's £2.50 more and I can't warrant the extra cost..
In reality £2.50 on the base price of a pen after investing your time in making the pen really isn't a point for discussion is it? OMHO..