In my eyes, a small-stack tournament heads-up set is:

40 x 5

40 x 25

20 x 100

and a large-stack tournament heads-up set is:

40 x 25

40 x 100

20 x 500

~or~

40 x 25

40 x 100

10 x 500

10 x1000

and combining those, I usually end up with:

40 x 5

40 x 25

40 x 100

20 x 500

10 x1000

or 150 total chips.

I run a lot of heads-up tournaments of varying types, so I have a bunch of heads-up sets -- and most of them are set up to handle both 5/25/100 and 25/100/500 stacks (see above). Here are a few starting stack variations:

A)

5/10 blinds, T1500 stacks (150BB):

20 x T5

20 x T25

9 x T100

-------------

49 chips = T1500

2 x T100 chips used to color-up T5 chips

(100 total chips in use)

B)

10/20 blinds, T2500 stacks (125BB):

20 x T5

20 x T25

19 x T100

-------------

59 chips = T2500

2 x T100 chips used to color-up T5 chips

(120 total chips in use)

C)

25/50 blinds, T7000 stacks (140BB)

20 x T25

20 x T100

9 x T500

-------------

49 chips = T7000

2 x T500 chips used to color-up T25 chips

(100 total chips in use)

D)

50/100 blinds, T12000 stacks (120BB)

20 x T25

20 x T100

9 x T500

5 x T1000

-------------

54 chips = T12000

2 x T500 chips used to color-up T25 chips

(110 total chips in use)

Variations A) and C) get used most often, for two reasons: largest number of starting big blinds, and requires one even rack per heads-up match. Versions B) and D) are actually better blind structures, imo. Of course, you can use nearly ALL of the chips heads up with 10/20 starting blinds and huge T12500 stacks (625BB), with 2 spare T100 chips to color-up the 5's.

I do have one 100-chip set that is constructed as follows:

40 x T25

40 x T100

16 x T500

4 x T1000

-------------

100 total chips

which uses 20/20/7/2 stacks (T8000) with 2 spare T500's to color up the T25 chips. But the rack isn't as pretty as the others.

It's pretty rare to get to the second color-up, so 5K plaques would typically not see any play -- unless you added them to the starting stacks.