Like most people in my age, I stumbled into wargaming through games like Hero Quest, Battlemaster and eventually 40K. I picked up some packs of cool looking figures when I was maybe 12-13. They turned out to be Space Marines.
That led to 14 years of gaming 40K (where I actually ended up fielding Eldar).
When Betrayal at Calth popped up I was immediately intrigued. I have no interest in 40K but I enjoy the fluff and I loved the Horus Heresy stuff. I picked up a box in the off chance I wanted do something with it (play another game using the models etc.)
In my head I immediately jumped back to Mentor Legion, discovered in an old White Dwarf I picked up at a used book store when I was a kid. Loved the paint scheme, loved the idea (veteran cadre, testers of all new military equipment, etc.). Not a normal Chapter by any stretch of the imagination.
I found some MkVI beakie heads and ordered up some fan-made jetpacks from Spellcrow in Poland (easy to find and purchase via ebay).
This is the end result. Possibly more coming in the future depending on how far I want to go with this stuff. I can see doing a few more squads and characters, maybe some terminators etc.
Now, for the purists...yes, none of it technically matches up. I wanted retro-beakie jump marines without spending a ton and this is the result: