I have seen many times "NEVER build a Small or Medium..."
I am not an expert player (I play since 2005 but never won a game yet) but I think the MDSF it is a useful ship and I always build many of it.
OK, the LDSF has lot of space, more fuel tank and can tow, but sometimes you don't have $ 600 to build two engines, some players prefer to build it with lower tech engine but I never do that (only with early Virgos to be towed by Cobols, or playing the Feds).
This ship can take all what a planet produced in one turn at midgame, when one of the minerals is exhausted, and go back with clans, it does not consume much fuel, it is very useful to colonize at early game: you can see in echoview the amount of clans needed in the planet to grow, this is always 11-19 so it can keep planets growing as it advances to the edge.
MDSF with Transwarp Engine:
$ 365 / DUR: 20 / TRIT: 7 / MOL: 41
LDSF with 2 Transwarp:
$ 760 / DUR: 117 / TRI: 13 / MOL: 78
Some races like Robots need an amazing amount of Duranium in their ship list.
Perhaps I am wrong and it's a waste of resources, but I think it's a useful ship, what do you think?
from far away planet Argentina
My races are Birds and Colonials.