This extension is only handy if you have a 1080 and not a 1400 (or don't want to use the longer one)... If I had realised that I had the 1400 hidden I would not have bought the shortie.

The only consolation for me is that my combinations of lengths have somewhat increased.

When you refer to the rubber edge strip, do you mean the "equivalent" of the Fe$tool clear plastic edge strip? The Fe$tool has not worn, however, I have used the same blade and do not flex/strees the saw when in use...
 Though a bevel cut should not affect it (the Fe$tool rail, at least according to Fe$tool) can't say for other brands.

Unfortunately I'm not a tracksaw aficionado... just a hack user that owns Fe$tool.

If your first cut is too short... Take the second cut from the longer end... LBD