I use silicone bass skirts in alot of ties, not positive, but always have assumed that 'sili legs' is just a specific brand or style of them?
I don't use them a whole lot for tails but i know others do with success. Using them for collars on jigs i end up cutting them both short and long - maybe just my own preference - but leave them long on large mouth jigs and cut them short for smallie jigs. Pictures make it easier to explain:
Largemouth Jig
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Smallmouth Jig (some of these smallie jigs have rubber skirt material which i have found i DO NOT like!

They stick/melt to everything)
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