MB, although I'm only an "untrustworthy" aerobatic type, please afford me the courtesy of quoting me fully and in context:
If you are on a long, high draggy final you may see the faster formation aircraft zip by you BUT they will break and extend downwind to allow you to land first.
I did say zip by you, not underneath you. You in your 45 knot machine would be given a safe half mile lateral seperation and would be quite safe.
Funny - I don't treat all microlighters with the same brush, even those that land unannounced on my strip and walk up asking for tea!
No - the dogs get those!
Stik