Agreed...joiner strips are one of the cleanest methods to joining fuselage sections.
And tabbed strips allow you to deal with varying section sizes.
Many models don't come with joiner strips, but they are easily made.
Heres some I did for a Mustang build.
First I lay out the fuselage parts on some card or paper and trace the outline.
From this you can rough out the joiner strip that matches the shape of the part properly.
This is important so the strip fits inside the part properly.
Allow for a solid half to fit inside the part...and a tabbed half to stick out from the part.
Its best to assemble your fuselage section first, and then fit the tabbed strips.
They will need to be shortened to fit the inside diameters.
If your aircraft has fuselage Formers, they usually fit at each seam,
so they will need to be re sized to fit inside the joiner strip.
You can fit the former before you attach the next fuselage section
or if you have enough access, you can fit the former after you join a pair of fuselage sections.